Spock v. Thanatos

[Jedi Master Spock]

Index:
Jedi Master Spock #1
Thanatos #1
Jedi Master Spock #2
Thanatos #2
Jedi Master Spock #3
Thanatos #3
Jedi Master Spock #4
Thanatos #4
Jedi Master Spock #5
Thanatos #5

The following message was the first e-mail in the debate between myself and Thanatos.

Opening statement:
I will begin by making a large number of assertions about VS arguments, about the particulars of each universe, and about the contrast of general ground warfare technology between Warhammer 40,000 and BattleTech. I expect you to challenge the points you do not agree with, but I expect you will agree with some statements in part or in full. I can provide evidence for each of my contentions, and will for each one that you choose to challenge rather than accept.

Game mechanics. In general, while game mechanics may be suspect, and may also be treated as a lower level than fluff or fiction, a certain amount of information may be extracted from game mechanics - at least where not contradicted by the fiction, fluff, other game mechanics, or physics, and always subject to resolution errors and poor approximations. However, both universes are best known for their games, and the games themselves contain information that may be buried deeply or not present within fiction or fluff.

• Warhammer 40,000: Qualitative, but not quantitative, information, within the resolution of the game system. As it is based on a complex D6 system (hit+wound+save Armor vs AP etc), quantitative information is subject to some inconsistencies, for example, in measuring relative strength with precision. E.g., the mechanic suggests an exponential scale for the strength of weapons, but the exponent is highly variable depending on choice of standard. However, we may determine:
  
  • Which weapons are stronger, at least within a given army, against general types of targets. For example, a bolter generally is better at hurting WH40K targets than a lasgun, but is also clearly a less potent weapon than a meltagun, regardless of the quirks in the approximation of the game system.
  • Which units are in general faster or slower units.
  • Which weapons have unusually long or short ranges.
  • Selection of inventory commonly in use within a given army.
  • Approximate physical scale of various objects.
  • Which units, within a given army, are tougher or more skilled.
  • Which weapons are fully automatic, slow to fire, difficult to aim, have collateral damage that will typically affect more than one infantryman in a tight formation, overheat badly, et cetera.
• BattleTech: Some quantitative information, some qualitative information, within the resolution of the game system. There are at least nine gaming systems in the franchise - Classic BattleTech, Solaris VII, BattleForce, AeroTech, BattleSpace, MechWarrior (RPG), MechWarrior (computer game), MechWarrior DA, and Battletech CCG, with numerous variants of each system. MWDA and the MW computer games do not appear considered canon by fans of the Classic BattleTech. The following data, however, appear consistent, to within rounding effects:
  
  • Quantitative strength of weapons vs BT targets (linear damage point values, rather than a weapon strength scale.)
  • Quantitative speeds of BT units.
  • Average number of hits to kill a given unit.
  • Relative armor strengths of units within a given unit type.
  • Waste heat generated by energy weapons (non-energy weapons' waste heat is treated inconsistently across different types of armored units, making it an iffier issue).
  • Mass spent per round of ammunition for a given weapon.

Basic principles:

• Parity of offensive and defensive systems. Units' standard equipment is usually sufficient to threaten damage to its primary targets, which are usually equal or larger size units. We may expect a priori that bolters threaten Space Marines, battle cannon threaten tanks, and particle projector cannons threaten BattleMechs. It is an exceptional circumstance for a unit to not carry weapons capable of providing a threat to itself, although the potency of the threat may vary; having such a weapon is thus, in the absence of other evidence, a reasonable assumption to make.
• Physics is a mature science. If the mechanisms are all understood, and no exotic mechanisms are actively in play, the results suggested by actual physics should be considered carefully.
• Consider recent warfare. Both universes are constructed with the assumption of prior human history and technology, at least up to the date publication began. Contrasts with modern technology can create numerous reductio arguments.
• Fiction is, as a rule, not as consistent as reality. See prior discussions of fan analysis and explanation complexity for details at length; in summary, we should both expect to discard some evidence as inconsistent.
• In the absence of direct evidence, scaling up or down from known data from related elements and known physics is usually one of the most appropriate methods of guessing performance. Care should be taken, of course; for example, a .30 caliber rifle does not have 8/27 of the muzzle energy of a .45 caliber pistol; caliber itself communicates relatively little information, so this error is expected.
• Assumptions should handle unknown material even-handedly. Example: If we have some unknown "supersonic" velocity, assuming for calculation this means Mach 1.001 in the BTverse ('minimal' supersonic) and Mach 3 ('average' supersonic) in WH40k in another part of your argument is inappropriate without additional supporting evidence.
• Slender, high-density kinetic weapons generally are the most energy-efficient means of punching a hole of given size through armor of a given thickness, followed fairly closely by HEAT type weapons, followed by short-period electromagnetic weapons (laser blasts). Explosives in general apply a mixture of thermal and kinetic energy; the ratio of energies depends on the type and yield of the explosion, although it is not unheard of for them to be evenly mixed.

Preliminary assertions:
These can be justified via a combination of fluff, fiction, and the above principles.

• Warhammer 40,000:
  
  • The lasgun has an actual effective yield on the close order of 2 megajoules in observed incidents, and a power pack with a rated capacity of 19 megajoules.
  • A bolter has a probable total yield per bolt, including kinetic and explosive energy, in either the e5 or e6 joule range. It is an automatic weapon, normally fed with magazines of 20-30 .75 caliber rocket-propelled explosive bullets.
  • The Earthshaker artillery cannon has ballistic performance similar to WWII-era artillery, with a 38 kg shell and a bit under 13 megajoules' muzzle energy, although it appears to have a superior bursting charge - approximately 2 gigajoules.
  • Regular tank guns have similar destructive power to modern tank cannons against buildings, and some appear to have a probable muzzle energy on the rough order of half that of the Earthshaker cannon while using standard munitions.
  • A normal lascannon fired under ordinary circumstances has a yield that is on the close order of, or below, 2 gigajoules, including no significant area effects; the rare laser destroyer, a more powerful weapon, is the least powerful laser weapon that causes collateral damage even on a direct hit.
  • A meltagun has an effective output-to-target most likely between 1 and 10 gigawatts. It is a broad-impact thermal weapon with limited range and ammunition.
  • Lascannon, battle cannon, meltaguns, and earthshaker cannon all have a fair chance of penetrating even Land Raider armor in a single hit. Other weapons with a reasonable chance of piercing any regular tank armor include Tau railguns and a variety of anti-tank missiles.
  • Total armor protection on a WH40K tank is not particularly impressive by modern standards and potentially vulnerable to single-hit kills from modern tank weapons.
  • Armor materials used in WH40K exceed modern armor materials per unit mass and per unit volume. In the special case of Space Marine vehicles, mounting advanced armor, standard composition appears to be typically comprised of a 20-25mm layer of radiation shielding/paint/environmental insulation, which has minimum effect against laser weapons and bullets, followed by a layer with very close to 5x the protection of conventional steel armor. Imperial Guard vehicles seem to have slightly thicker armor layers, but do not enjoy superior protection as a consequence of these thicker layers.
  • The primary armored vehicle chassis for the Imperial Guard, which are the Imperium's primary users of armored vehicles, has a maximum off-road speed of 21 kph. On the road, it still only goes 35 kph, about the speed of a running Space Marine.
  • Powered battle armor have not been witnessed surviving the application of gigajoule-energy weapons.
  • Titans have powerful void shields that regenerate fairly quickly.
• BattleTech:
  
  • A particle projector cannon's shot puts out a total energy in the e10 joule order of magnitude, and causes significant harm to infantry who happen to be simply near the target. The large laser is not far off from this and similarly causes lethal thermal effects on nearby humans. Even small/medium grade lasers have been observed causing significant destruction in the e9 joule range.
  • A standard gauss rifle is a 100mm 125kg caliber hypersonic solid slug of some ferromagnetic material with a kinetic energy of 720-1000 megajoules, and enough momentum to cause a BattleMech to skid, plow, or lurch multiple meters. The muzzle velocity of other gauss weapons is similar, although not necessarily exactly the same.
  • The gauss rifle described above will either barely pierce or barely be stopped by a 10 gram/cm^2 layer of BT armor.
  • Armor used on BattleMechs generally exceeds the penetration of modern tank rounds by a comfortable margin.
  • BattleMechs are quite nimble, and have superior mobility to tanks with similar top speeds.
  • Powered battle armor mount weapons that are on par with the very lightest weapons used on BattleMechs.
  • Most BattleMechs have a rated top speed between 60 and 100 kph. Most tanks also fall in this range.
  • One heat point in the game from an energy weapon represents on the close order of one gigajoule of waste heat.
  • Damage value is in general proportionate to armor shattered (kinetic weapons) melted/vaporized (thermal weapons), or a combination of the two (explosive weapons).
  • BattleTech battle armor and BattleMechs tend to be jump-capable, like Tau crisis suits.
  • The high explosive component of BattleTech autocannon shells accounts for the majority of their destructive effect against BattleMechs. The precise explosive mechanism of these uranium-tipped supersonic shells may vary.
• Comparing the two, we find that:
  
  • Downsizing the BattleTech gauss technology to a 1 point or 2 point weapon leaves it with enough armor penetration to threaten a Land Raider regardless of choice of scaling factor. As gauss weapons in this damage range exist, and are deployed by battle armor, gauss-armed BattleTech battle armor units are capable of piercing Land Raider armor.
  • Based on the above information about energy weapons, and game mechanical information accounting for resolution error, the small laser almost certainly exceeds 2.3 GJ, which in turn means it has a higher yield than the lascannon, which threaten Land Raiders via the same mechanism (concentrated laser energy). This means that small-laser armed BattleTech battle armor units are capable of defeating Land Raider armor.
  • The first two items suggest a general case, which is to say that nearly all BattleTech battle armor (excluding a handful of light models that do not always mount full-strength anti-BattleMech weapons) can individually threaten Warhammer 40,000 vehicles up to and including the Land Raider.
  • The PPC is at least five times as powerful as the lascannon and has fringe thermal effects. Land Raider armor will not handle this, although it is possible that a few Space Marine passengers will survive the destruction of their transport and the rest of their squad.
  • The full strength gauss rifle is wasted on the Land Raider, as the majority of its kinetic energy is likely to exit the opposite side of the vehicle.
  • From these two examples, we may conclude BattleMechs' primary weapons, which are also the primary weapons of heavier tanks in the BTverse, are likely to mission-kill Warhammer 40,000 conventional tanks with any direct hit, even at extreme range for the weapon or a relatively poor angle of impact with the armor.
  • The fact that BattleTech battle armor very often survives hits from energy (high velocity particle and laser) weapons that would kill a Space Marine outright (or a even Warhammer 40,000 tank) demonstrates superior protection against concentrated thermal attacks, as well as superior durability of PBA suits.
  • The fact that a ridiculously thin layer of BattleTech armor can halt a hypersonic projectile with enough momentum to cause a 100 ton BattleMech to stagger or skid multiple meters demonstrates extraordinarily superior protection against kinetic attacks, as well as the superior durability of the BattleMechs and BattleTech armored vehicles that handily survive multiple attacks from weapons that make a mockery out of the Land Raider's adamantium-ceramite alloy shell.
  • Since the top rated combat speeds of most BattleMechs and BattleTech tanks exceeds the maximum off-road tank speed of the Imperial Guard's common Leman Russ tanks by a factor of three to five, the Imperial Guard is terribly outpaced on the march and in the field.
• Sample unit comparison between a BattleMech and Warhammer 40,000 tank. Both are sixty tons; we compare the stock Leman Russ to the 3025-era Kuritan staple, the DRG-1N Dragon. The Leman Russ is plainly the inferior war machine - and also far more realistic to our modern eyes, not coincidentally:
  
  • Main weaponry:
    
    • Leman Russ: Battle Cannon (40 rounds)
    • Dragon: AC/5 (40 rounds) - this is a fair match for the Battle Cannon.
    • Dragon also has LRM-10 (24 rounds) - slightly more powerful weapon capable of indirect fire from out of sight, but which cannot lock onto close targets effectively.
  • Secondary weaponry:
    
    • Leman Russ: 1 lascannon
    • Dragon: 2 medium lasers - each of which is more powerful than the lascannon
  • Mobility:
    
    • Leman Russ: 35 kph on the road, 21 kph in the field. Capable of scaling hills, rolling over small obstacles/pits, fording streams, churning through meter-deep mud, etc. Turns slowly. Does not shoot well on the move (see Conqueror variant).
    • Dragon: 86 kph rated maximum speed. Capable of stepping over large obstacles, climbing cliffs, extended underwater operations, wading through mud deep enough to completely immerse a tank, etc. Pivots on a dime; usually fires on the move.
  • Armor:
    
    • Leman Russ: Vulnerable to single hits from own weapons. Surviving multiple hits from own weapons unlikely.
    • Dragon: Unlikely to be destroyed by single hits by weapons half an order of magnitude more powerful than own weapons. Surviving more than a dozen hits from own weapons very likely.
  • Personnel commitment:
    
    • Leman Russ: Crew of 4.
    • Dragon: Crew of 1.

[Thanatos]

Opening statement:Game mechanics. In general, while game mechanics may be suspect, and may also be treated as a lower level than fluff or fiction, a certain amount of information may be extracted from game mechanics - at least where not contradicted by the fiction, fluff, other game mechanics, or physics, and always subject to resolution errors and poor
approximations.

I'm going to stop you right here on the 40K front. As I said before, the tabletop rules are not canon for obvious reasons.

For example, under the new rules a glancing hit has been reducing in effectiveness by 30% and can no longer destroy a vehicle. Did armor get considerably tougher? No, because the game data does not reflect the source because of balance concerns.

How balanced? The movie marines list from the German White Dwarf recreated fluff marines on table top and they had characteristics close to that of the table tops medium armor. I seem to remember telling you all this before.

Preliminary assertions:
These can be justified via a combination of fluff, fiction, and the above

principles.

Finally getting to some meat here. One thing I would ask: Could you stop mixing units and notation? You go from saying kilojoules to using joules with scientific notation instead of kilojoules, then skip over to megawatts for a thermal weapon.

* Warhammer 40,000:
o The lasgun has an actual effective yield on the close order of 2 megajoules in observed incidents, and a power pack with a rated capacity of 19 megajoules.

Close enough to not bother arguing, although it should be noted there's a wide variety of lasguns and lasgun settings.

o A bolter has a probable total yield per bolt, including kinetic and explosive energy, in either the e5 or e6 joule range. It is an automatic weapon, normally fed with magazines of 20-30 .75 caliber rocket-propelled explosive bullets.

This is quite a bit off since modern rifle rounds of similar caliber and velocity to the 8.25mm autogun are in the the 5-6KJ range.

o The Earthshaker artillery cannon has ballistic performance similar to WWII-era artillery

Actually, it has performance far superior to WW2 arty. You grabbed your figures from one of the IAs but seem to have mysteriously left out the muzzle velocity of 814 meters per second which translates to a range of around 70km.

For comparison sake, the M107 HE is the standard modern 155mm round and it has a muzzle velocity of 540m\s and a 42kg warhead and has a range of 15km. Which is probably where the incorrect 15km range figure comes from, IA is notoriously inconsistent.

o Regular tank guns have similar destructive power to modern tank cannons against buildings.

Modern guns are well below the level of 40K guns. The Conquerers gun had a recoil force of 190 tonnes while a modern 120mm has a recoil force of 56 tonnes. Shell effectiveness and ammunition type play a part.

Keep in mind this is the light cannon version of the Leman Russ and that's just the recoil force. Also remember that tank guns are far more powerful than arty guns.

,and some appear to have a probable muzzle energy on the rough order of half that of the Earthshaker cannon while using standard munitions

Actually, like modern tanks they have far greater muzzle energy than artillery. So already we can see you're way off track on tank guns and how they stack up.

o A normal lascannon fired under ordinary circumstances has a yield that is on the
close order of, or below, 2 gigajoules, including no significant area effects

I find this highly spurious, as your previous calcs using supposition that reduced the yield, resulted in a figure of 6 gigajoules. Where did you pull this lower figure from? Especially since Hellguns are in the low to mid range double digit MJ according to IA5 and events from fluff. And they don't stack up well compared to multilasers, much less lascannons.

o A meltagun has an effective output-to-target most likely between 1 and 10
gigawatts.

Meltas can vaporize whole swaths of troops with a single burst and cause flashburns from superheated air.

Jurgen's melta ripped a ragged hole through their lines, vaporising flesh and bone, to leave a narrow corridor of flash-burned victims writhing and screaming on either side where the air around the superheated plasma burst had scorched and seared them, and the rest of us opened up on the survivors to widen it

Triple MJ to single GJ secondary effects.

And a Melta is an inferior AT weapon compared to the Lascannon. Jurgen has to aim for a weak spot to disable the track of a Leman Russ. In storm of Iron multimeltas rated at high double GJ were unable to directly destroy a Demolisher and only succeeded because they managed to melt the barrel without the TC knowing when he fired.

It is a broad-impact thermal weapon with limited range and ammunition.

Limited ammunition? Where do you get that from?

o Lascannon, battle cannon, meltaguns, and earthshaker cannon all have a fair chance of penetrating even Land Raider armor in a single hit. Other weapons with a reasonable chance of piercing any regular tank armor include Tau railguns and a variety of anti-tank missiles.

This seems rules pulled. In fluff, only high end AT weapons have any near guarantee of a first round kill.

o Total armor protection on a WH40K tank is not particularly impressive by modern standards and potentially vulnerable to single-hit kills from modern tank weapons.

That's because you're using the "conventional steel" quote out of context purposely. Any quote referring to "conventional steel" is done by in universe fluff and refers to Plasteel which is the metallic material in common usage on Imperial vehicles.

Any calc using the assumption of RHA is flawed to begin with.

o Armor materials used in WH40K exceed modern armor materials per unit mass and per unit volume. In the special case of Space Marine vehicles, mounting advanced armor, standard

composition appears to be typically comprised of a 20-25mm layer of radiation hielding/paint/environmental insulation, which has minimum effect against laser weapons and bullets, followed by a layer with very close to 5x the protection of conventional steel armor.

Again, its refferring to the plasteel armor on the Leman Russ.

o The primary armored vehicle chassis for the Imperial Guard, which are the Imperium's primary users of armored vehicles, has a maximum off-road speed of 21 kph. On the road, it still only goes 35 kph, about the speed of a running Space Marine.

Actually, there is plenty of evidence of extreme speed governors, which are routinely removed by crews (known in universe as being overcharged) despite being forbidden by regulations.

Well standard on paper, the hand-picked crews had tinkered and modified the tanks

over the last three months of war, and he expected a tech-priest would have a heart attack

if one ever saw some of the changes they'd made.
----
The comms set was squawking nonsense as he pressed it hard against his ear, trying to listen over the clanking of tracks and the rumbling of the big overcharged engine of the

Vanquisher.

There's a good amount of inference at them being able to pull modern speeds easily when properly tuned.

That's ignoring all the contradictions in IA itself in the statistics from vehicle to vehicle much less compared to the rest of the universe, as I mentioned before. Which is ironic, as I seem to remember you having problems with a book that you believed to be non reflective of the universe in question.

Incredible something or other?

o Powered battle armor have not been witnessed surviving the application of
gigajoule-energy weapons.

Depends really on the type of armor. There have been numerous GJ events, from repeated Hellgun fire to close range plasma detonation.

o Titans have powerful void shields that regenerate fairly quickly.

OK?

* BattleTech:
o A particle projector cannon's shot puts out a total energy in the e10 joule order of

magnitude, and causes significant harm to infantry who happen to be simply near the target.

The large laser is not far off from this and similarly causes lethal thermal effects on

nearby humans. Even small/medium grade lasers have been observed causing significant

destruction in the e9 joule range.
o A standard gauss rifle is a 100mm 125kg caliber hypersonic solid slug of some

ferromagnetic material with a kinetic energy of 720-1000 megajoules, and enough momentum to

cause a BattleMech to skid, plow, or lurch multiple meters. The muzzle velocity of other

gauss weapons is similar, although not necessarily exactly the same.
o The gauss rifle described above will either barely pierce or barely be stopped by a 10

gram/cm^2 layer of BT armor.
o Armor used on BattleMechs generally exceeds the penetration of modern tank rounds by a

comfortable margin.
o BattleMechs are quite nimble, and have superior mobility to tanks with similar top speeds.
o Powered battle armor mount weapons that are on par with the very lightest weapons used on

BattleMechs.
o Most BattleMechs have a rated top speed between 60 and 100 kph. Most tanks also fall in

this range.
o One heat point in the game from an energy weapon represents on the close order of one

gigajoule of waste heat.
o Damage value is in general proportionate to armor shattered (kinetic weapons)

melted/vaporized (thermal weapons), or a combination of the two (explosive weapons).
o BattleTech battle armor and BattleMechs tend to be jump-capable, like Tau crisis suits.
o The high explosive component of BattleTech autocannon shells accounts for the majority of

their destructive effect against BattleMechs. The precise explosive mechanism of these

uranium-tipped supersonic shells may vary.

Evidence needed.

* Comparing the two, we find that:
o Downsizing the BattleTech gauss technology to a 1 point or 2 point weapon leaves it with

enough armor penetration to threaten a Land Raider regardless of choice of scaling factor.

As gauss weapons in this damage range exist, and are deployed by battle armor, gauss-armed

BattleTech battle armor units are capable of piercing Land Raider armor.
o Based on the above information about energy weapons, and game mechanical information

accounting for resolution error, the small laser almost certainly exceeds 2.3 GJ, which in

turn means it has a higher yield than the lascannon, which threaten Land Raiders via the

same mechanism (concentrated laser energy). This means that small-laser armed BattleTech

battle armor units are capable of defeating Land Raider armor.
o The first two items suggest a general case, which is to say that nearly all BattleTech

battle armor (excluding a handful of light models that do not always mount full-strength

anti-BattleMech weapons) can individually threaten Warhammer 40,000 vehicles up to and

including the Land Raider.
o The PPC is at least five times as powerful as the lascannon and has fringe thermal

effects. Land Raider armor will not handle this, although it is possible that a few Space

Marine passengers will survive the destruction of their transport and the rest of their

squad.
o The full strength gauss rifle is wasted on the Land Raider, as the majority of its kinetic

energy is likely to exit the opposite side of the vehicle.
o From these two examples, we may conclude BattleMechs' primary weapons, which are also the

primary weapons of heavier tanks in the BTverse, are likely to mission-kill Warhammer 40,000

conventional tanks with any direct hit, even at extreme range for the weapon or a relatively

poor angle of impact with the armor.
o The fact that BattleTech battle armor very often survives hits from energy (high velocity

particle and laser) weapons that would kill a Space Marine outright (or a even Warhammer

40,000 tank) demonstrates superior protection against concentrated thermal attacks, as well

as superior durability of PBA suits.

Going to need to see proof of all of this. You especially need to prove that the game data matches the universe and back up any calcs with fluff.

o The fact that a ridiculously thin layer of BattleTech armor can halt a hypersonic

projectile with enough momentum to cause a 100 ton BattleMech to stagger or skid multiple

meters demonstrates extraordinarily superior protection against kinetic attacks, as well as

the superior durability of the BattleMechs and BattleTech armored vehicles that handily

survive multiple attacks from weapons that make a mockery out of the Land Raider's

adamantium-ceramite alloy shell.

And this. Especially since Imperial Guard vehicles have withstood the same thing on their side armor.

Re-laying the gun took a vital second. In that time, the second tank fired again and hit the Wrath squarely. The impact was enough to lurch all sixty-two tonnes of armoured machine several metres sideways. But it didn't penetrate the twenty centimetre-thick armour skin.

Inside, the crew were dazed and they'd lost most of the forward scopes."

* Sample unit comparison between a BattleMech and Warhammer 40,000 tank. Both are sixty tons; we compare the stock Leman Russ to the 3025-era Kuritan staple, the DRG-1N

Dragon. The Leman Russ is plainly the inferior war machine - and also far more realistic to our modern eyes, not coincidentally:

Matter of opinion till otherwise backed up.

+ Dragon: AC/5 (40 rounds) - this is a fair match for the Battle Cannon.

Again with the proof needed.

+ Dragon: 2 medium lasers - each of which is more powerful than the lascannon

Again, proof needed.

o Mobility:
+ Leman Russ: 35 kph on the road, 21 kph in the field. Capable of scaling hills, rolling over small obstacles/pits, fording streams, churning through meter-deep mud, etc. Turns slowly. Does not shoot well on the move (see Conqueror variant).

Ignoring the bits about speed I commented on before: I have no clue where you got the idea it turned slowly. It can also go through far higher than meter deep mud since its got a great deal of torque among other features, such as legendary reliability.

You are also incorrectly referencing the Conquerer part of IA: It was found that it had better accuracy on the move because it had a better stabilizer.
The description of the arch-enemies knock off Leman Russ and how it relates to the Conqueror

LeGuin had it right. Examples of old, sub-Imperial standard technology, the Reavers lacked any auspex guidance or laser rangefinding. It was also clear they had no gyro stabilizers. Once the Conqueror guns were aimed they damn well stayed aim-locked thanks to inertial dampers, no matter how much bouncing and lurching the tank was experiencing. That meant the Conquerors could shoot and move simultaneously without any appreciable loss of target lock. The AT70s fired by eye and any movement or jarring required immediate aim revision.

They're also noted as having inferior armor, poorer rate of fire and haphazard cross country performance compared to a Russ.

They get a big brother later that tries to copy the Leman Russ

Hurling specialist AT shells, the three Imperial tanks got down to business, their first three or four salvoes turning the Blood Pact's well-ordered chase advance into a bloody riot. The Wild One crippled one of the big AT83s with its first shot and killed it with its second. The AT83 Brigands, larger than their more primitive cousins the 70s, were, on paper, the Urdeshi forge world's equivalent of the Leman Russ. They had auspex guidance, weapon stabilisers and torsion bar suspension. They were the Blood Pact's best battle machines, not counting the very few ancient super-heavies they had inherited from defeated Guard units."

+ Dragon: 86 kph rated maximum speed. Capable of stepping over large obstacles,

climbing cliffs, extended underwater operations, wading through mud deep enough to completely immerse a tank, etc. Pivots on a dime; usually fires on the move.

Unfortunately its also a mech, with all the tremendous flaws that come along with that. Here's a hint: Its going to suck at everything you think its going to be good at. Oh I'm sure its probably done some of those in fluff, but in any realistic environment its boned.

o Armor:
+ Leman Russ: Vulnerable to single hits from own weapons. Surviving multiple hits from own

weapons unlikely.

Requiring multiple hits to kill is actually standard for the Leman Russ.
A couple examples:

An AT70 lobbed a shell at the Wild One that tore away its sponson and part of its track skirt. Another hit the Demands With Menaces on the turret destroying its vox-mast, pintle mount and laser range-finder, and killing the assistant gunner with explosive spalling.

Wounded but not down, the Demands With Menaces plunged forward, laying its guns at the Reaver responsible. Corbec saw the top-hatch pop and the commander emerge, oblivious to the danger, to verify aim with a handscope now his range-finder was

Emboldened by the sight of a Leman Russ burning, the Brigand stirred forward again, and hammered a shot at the Access Denied that crushed its front bracings and fore-hull plating.

There's also a volume of examples in Honour Guard where concentrated fire is required to take down a Russ. That includes main gun and lascannon fire.

+ Dragon: Unlikely to be destroyed by single hits by weapons half an order of

magnitude more powerful than own weapons. Surviving more than a dozen hits from own weapons

very likely.

That's because its own weapons are underwhelming for the weight class its in.

o Personnel commitment:
+ Leman Russ: Crew of 4.
+ Dragon: Crew of 1

Clearly goes in the Leman Russ' favor if you know anything about ground combat.

[/quote]

[Jedi Master Spock]

I'm going to stop you right here on the 40K front. As I said before, the tabletop rules are not canon for obvious reasons.

For example, under the new rules a glancing hit has been reducing in effectiveness by 30% and can no longer destroy a vehicle. Did armor get considerably tougher? No, because the game data does not reflect the source because of balance concerns.

How balanced? The movie marines list from the German White Dwarf recreated fluff marines on table top and they had characteristics close to that of the table tops medium armor. I seem to remember telling you all this before.

Hence why I said only qualitative information held, and only within a given army. Because the system is prone to large rounding errors and large errors based on "minor" balance adjustments, quantitative data (like saying armor just got 30% tougher) is impossible.

It's not even clear from the game that the Leman Russ and the Land Raider, from two different armies, both with AV14, have anywhere near equal armor. I see no reason, even from what you're saying, why I might not simply conclude - in the absence of other information, straight from the game mechanics - that Conqueror < Battle Cannon < Earthshaker < Demolisher in damaging effect, or that the Leman Russ is more heavily armored than the Chimera, or that the Laser Destroyer is more powerful than the Lascannon, which is more powerful than the Lasgun.

I also notice you have offered nothing in BT to dispute my treatment of mechanics there.

A bolter has a probable total yield per bolt, including kinetic and explosive energy, in either the e5 or e6 joule range. It is an automatic weapon, normally fed with magazines of 20-30 .75 caliber rocket-propelled explosive bullets.

This is quite a bit off since modern rifle rounds of similar caliber and velocity to the 8.25mm autogun are in the the 5-6KJ range.

If I were talking about the 8.25mm autogun:

The simple technology required to manufacture autoguns makes them common on frontier worlds where contact with the Imperium is infrequent, and also with gang members on Hive-worlds. As a weapon, the autogun is comparable in effectiveness to a lasgun but lacks some of the lasgun's versatility and reliability.

This particular autogun fires a long 8.25 caliber round, on either single shot, semi-automatic, and fully automatic, with a cyclic rate of 650 rounds per minute with a muzzle velocity of 820 meters per second.

I would be quite a bit off. The Space Marines' bolter, however, is a larger and more powerful weapon, and fires high-explosive shells.

Actually, it has performance far superior to WW2 arty. You grabbed your figures from one of the IAs but seem to have mysteriously left out the muzzle velocity of 814 meters per second which translates to a range of around 70km.

Assuming g=9.8m/s^2, and no air resistance, the range is a hair under 68 km. However, neglecting air resistance gives pretty poor precision past 30 m/s, and absolutely terrible results past Mach. Air resistance increases with speed, meaning that you get less and less out of increasing muzzle velocity.

As indicated here, a WWII-era 134mm naval gun used by the British, firing a 36.3 kg shell at 792 m/s, had a range of 21 kilometers. The Bofors 40mm gun, with more surface area, only had a ~10 kilometer maximum range in spite of a ~900 m/s muzzle velocity. Shell ballistics, rather than muzzle velocity, are the main limitation on range - very clearly, shells used by the Imperial Guard have poor ballistics. Please note, incidentally, from that website:

This was a somewhat large caliber for a DP gun, but chosen because it was considered that this size would provide the maximum weight of shell that could still be manually handled by the average gun crew.

This will be important later. The 15-16 km range figure is repeated in Imperial Armour volumes I, III, and V, in narration as well as fluff text.

The Earthshaker is a 132mm calibre weapon, capable of firing a shell over 15 kms at a velocity of 814 mps. Such is the power of Earthshaker shells that they are easily capable of destroying enemy vehicles, strongpoints, or buildings.

The cannon itself is a model of reliability and consistency. Using its standard 5 powder charges, the Earthshaker can reach out to approximately 16 km with a 38 kg shell. Earthshakers mounted on platforms are sometimes issued with charges 6 and 7, in an attempted to increase this range. This induces considerable strain and eventually leads to erosion of the firing chamber so that correctly sealing the breach before firing becomes impossible. Firing charges 6 and 7 is occasionally allowed, but must be authorized by high command, and is only used with good reason. Not more than twenty rounds are allowed through any given gun, and crews often keep a tally of overcharged shells on the gun itself. Basilisks do not use overcharging, as the Chimera chassis is not considered stable enough, making shots wildly inaccurate.

The Earthshaker cannon is a 132mm calibre weapon, capable of firing a shell over 15 kms at a velocity of 814 mps. Such is the power of the gun that it is easily capable of destroying enemy armoured vehicles, strong points and buildings. Fired using the standard 5 charges, an enclosed Basilisk cannot use the larger charges 6 and 7, due the recoil restriction of the fighting compartment. This slightly limits the gun's maximum range when compared to open-topped or platform-mounted Earthshakers.

Heavy Earthshaker barrels were raised to the sky... Nearly fifteen kilometers away the shells landed with a splintering crash...

The Earthshaker is the Imperial Guard's standard artillery piece. It is a 132mm calibre weapon, capable of firing a 38 kg shell at a velocity of 814 mps. So a shell fired to maximum range would take 19 seconds from firing to impact. The cannon itself is a model of reliability and consistency. It uses its standard five powder charges, but this can be increased with the addition of charges six and seven. This will increase the range at the risk of additional wear and stress on the gun itself... No gun may fire more than twenty overcharged rounds.

For comparison sake, the M107 HE is the standard modern 155mm round and it has a muzzle velocity of 540m\s and a 42kg warhead and has a range of 15km. Which is probably where the incorrect 15km range figure comes from, IA is notoriously inconsistent.

I doubt the 15 km range was pulled specifically from the M107, although it's possible. Muzzle velocity and range were probably both pulled from a lighter gun. Note that the only source I could find disputing the 814 m/s muzzle velocity was the outdated "Imperial Armour":

CALIBER: 12.5cm
MUZZLE VELOCITY: 410 mps

It also gave a barrel length of 9.00m, which I will assume is accurate, but I believe the more recent sources qualify as a retcon. They're really remarkably consistent in how they describe the Earthshaker.

Modern guns are well below the level of 40K guns. The Conquerers gun had a recoil force of 190 tonnes while a modern 120mm has a recoil force of 56 tonnes. Shell effectiveness and ammunition type play a part.

Depends on how we choose to measure recoil force. The Conqueror has a very short barrel proportionate to its diameter, meaning a light gun relative to the shell, meaning more kinetic energy applied to the recoiling barrel.

It also means the force on the bullet and the barrel itself are being applied over a shorter distance; the Conqueror barrel is 2.49m (Imperial Armour) while the Abrams barrel, a sample modern tank barrel, is 9.77m. 190T*2.49m=473T*m; 56T*9.77m=548.8T*m - that's 16% more energy.

Furthermore, the above citations make it clear that the Earthshaker operates at close to the maximum recoil of the Chimera chassis, which also constrains the force of WH40K tank guns.

Third, we have this lovely description:

The demolisher cannon is used to blow passageways through the walls of buildings and the assault dozer is used to bull its way through obstacles and smaller structures... [the Codex] advises a Space Marine squad should advance from building to building by blasting holes in the walls of adjacent buildings, after their supporting Vindicator, outside in the street, brings the target building under devastating close range fire.

Blowing man-sized holes in walls is within the capabilities of modern MBT guns.

Actually, like modern tanks they have far greater muzzle energy than artillery. So already we can see you're way off track on tank guns and how they stack up.

Assuming the Conqueror manages to apply a peak 190 tonne force for the whole 2.49m length of its barrel, it has a muzzle energy of 4.6 megajoules. The Earthshaker, as described above, has a muzzle energy of 12.6 megajoules.

Keep in mind this is the light cannon version of the Leman Russ and that's just the recoil force. Also remember that tank guns are far more powerful than arty guns.

Not necessarily. It depends on the type of artillery. Close naval fire support, for example, has usually involved guns much more powerful than tank guns. Also note that even the 155m shell you described has a muzzle energy of 6.1 megajoules - not terribly far from a modern kinetic penetrator.

I find this highly spurious, as your previous calcs using supposition that reduced the yield, resulted in a figure of 6 gigajoules. Where did you pull this lower figure from? Especially since Hellguns are in the low to mid range double digit MJ according to IA5 and events from fluff. And they don't stack up well compared to multilasers, much less lascannons.

My calculations were that if lascannons could perform a feat I have never seen them perform, then they could have a yield of that much. Please do cite specific quotes when you make claims. As it so happens, IA5 supports something smaller:

The standard armament of the grenadier squads is the type XIV lasgun (heavy), referred to by troops as the 'hellgun' or, more rarely 'hotshot' lasgun. In effect this is an overpowered lasgun, firing in the 28 megathule range and incorporating many additional features. The weapon's powerpack is worn as a backpack, and the power cables run to the weapon's rapid discharge generator, which forms the weapon's main mechanism, where energy for each shot is fired. The heavy powerpack supplies enough power to keep the weapon firing for two hundred shots, depending on the power settings and the weapon's condition.

Most generous interpretation: 28 MJ/shot * 200 shots = 5.6 GJ. Considering the man-portable scale of the lascannon, and the size of the power pack displayed on the Space Marine-portable variant, I expect at least three shots per infantryman's-backpack of power pack. There is, of course, also Azazel's spread:

Laser Generator: 3.9 megawatts

Laser generator capable of full charge from dead in 2 hours, good for 1 hour of full combat.

28-42 GJ expended in an hour of combat, depending on whether or not the generator operates during combat or not. Anything less than one shot per 85 seconds falls under 2 GJ consumed per shot, which is definitely less than 2 GJ delivered to target.

Third: For a gigajoule-range weapon applying its energy to a small volume in a fraction of a second, common accidental targets (including boulders, humans, and trees) will superheat into vapor and kill nearby unarmored infantry. We see no such collateral damage in the game, nor in any description of lascannon firing I have yet witnessed.

Meltas can vaporize whole swaths of troops with a single burst and cause flashburns from superheated air.

Jurgen's melta ripped a ragged hole through their lines, vaporising flesh and bone, to leave a narrow corridor of flash-burned victims writhing and screaming on either side where the air around the superheated plasma burst had scorched and seared them, and the rest of us opened up on the survivors to widen it.

Triple MJ to single GJ secondary effects.

(Please indicate which novel this quote is from. That's a whole series to sort through.) Not secondary, total effects. With an extended burst. Moreover, we have two better examples.

His voice was drowned out by the abrupt hiss of the melta as Jurgen fired into the wall, instantly flashing a dozen cubic meters of ice into steam, which condensed almost instantly in the subzero temperatures, filling the narrow passageway with mist.

30-40 gigajoules delivered to target, depending on overheat. 19,000+ cubic meters of steam generated in a narrow passageway, also depending on overheat. No violent overpressure, so this should be a pretty long "instant." 1-10 GW and a relatively wide passageway still give fairly violent winds.

They captured an entrance to a personnel shelter and, after a melta-gun blasted the steel door into molten metal, Tyborc led them down the ferrocrete steps into the bunker below.

Note the lack of vaporized metal and the ability of Imperial Guards to follow the melta-blast closely. If the steel door is 100-1000 kg and more or less given minimal energy to melt in a 0.1 second blast, this is 1-10 GW.

With a roar of super-heated air the melta-gun hit, and whatever it was lurking in the darkness died, turning into a slimy pile of oozing ichor by temperatures that could melt plasteel in a second.

Much the same.

And a Melta is an inferior AT weapon compared to the Lascannon. Jurgen has to aim for a weak spot to disable the track of a Leman Russ.

Quote?

In storm of Iron multimeltas rated at high double GJ were unable to directly destroy a Demolisher and only succeeded because they managed to melt the barrel without the TC knowing when he fired.

Rated at double digit GJ where?

Limited ammunition? Where do you get that from?

It's a weapon that fires a stream of superheated gas.

This seems rules pulled. In fluff, only high end AT weapons have any near guarantee of a first round kill.

Guarantee? Of course not. Strong possibility? Thus speaks the fluff:

The lascannon fires a powerful blast of laser energy capable of cutting through the thickest armour plating.

Within the gun itself is a laser chamber that charges an explosive energy blast capable of blasting apart any enemy vehicle.

Now, it may not be able to pierce Land Raider armor at a very wide range of angles, but it can indeed do so. Tau railguns, however, seem in particular effective:

No Imperial commander had ever encountered this new mark of Tiger Shark before... Missiles rippled from the aircraft's wings, flaring bright against the Warhound Advensis Primaris' void shields. The explosions overpowered the generators which cut out. The following shots from the Tiger Shark's twin railguns struck the Warhound squarely in the hull. With devastating power two hyper-sonic shots tore through the thick armour plates in an explosion that showered the surrounding desert in molten shrapnel. Critically wounded the Warhound staggered backwards under the impacts, tottered and, to the astonishment of all, fell. Where once Imperial commanders had thought the Titans untouchable to all but a Manta's firepower, suddenly the Tau had a new tactical weapon capable of killing the mighty war machines.

On the battlefield, the Broadside is a tank-hunter. Its railguns can cut through almost any armour, and it is small enough to utilize cover well. The distinctive whip-crack sound and hyper-sonic speed of a railgun became synonymous with the desert fighting on Taros.

Our tanks were useless. As soon as we broke cover, their battlesuits' heavy guns were locked onto us. I swear it was as though they had someone nearby aiming for them before they shot. And when they did shoot... Emperor's mercy! Their guns punched through our armour like it was paper. All I could see were trails of fire where the projectiles had ignited the air.

And of course, the heavier guns - the Demolisher, Earthshaker (quoted above), Vindicator (see below), etc - do so pretty well:

Though short-ranged, the Vindicator's Demolisher cannon is capable of destroying enemy armour and fortifications in a single shot.

That's because you're using the "conventional steel" quote out of context purposely. Any quote referring to "conventional steel" is done by in universe fluff and refers to Plasteel which is the metallic material in common usage on Imperial vehicles.

I'm going to have to have a source for that - and it better be a good one, because I already have a quote that contradicts that claim:

Due to its STC roots the Rhino can be constructed using locally available materials. Most Rhinos are constructed of a bonded ceramite layer over a cast plasteel hull, although others use carbon composite compounds or conventional hardened steel, depending on their origin.

The Rhino is usually constructed with plasteel... but can be constructed using conventional hardened steel.

On top of that, plasteel can be forged by hand:

Not being front line combat troops, the garrison auxilia were not generally issued with any form of body armor, and this trooper has corrected this with hand-forged plasteel plates. These will provide rudimentary protection in battle, especially in hand-to-hand combat, but also against lasgun rounds.

On top of that:

Such is the power of the gun and the sophistication of the ammunition that there is no known armour a Vanquisher cannon cannot penetrate, even the thick armour of a Titan can be punctured.

Also called sub-calibre munitions, high velocity anti-tank shells or 'Vanquisher' shells (because they are only fired by the Leman Russ Vanquisher tank). A Vanquisher shell is a solid dart of super dense metal contained within a lightweight 'shoe' or case. The dart is only about a third the calibre of the actual shell (hence sub-calibre). Once fired, the case will drop away leaving just the speeding dart.

BARREL LENGTH: 6.50m

A relatively primitive version of the modern discarding-sabot round. The high-density segment is 3.5 (sub)calibers long, and tipped with a ballistic cap that extends the projectile 1 more caliber. Assuming mostly depleted-uranium construction, and a caliber of 40mm (one third of 120mm) gives a ~10 kg sabot. Modern discarding-sabot projectiles are smaller, but narrower, with similar density of kinetic energy assuming similar velocity (reasonable given the Earthshaker data) and better flight characteristics (fin stabilized) meaning better penetration under the standard models for handling high-velocity projectiles.
Vanquisher rounds do have a higher energy, and will therefore cause more damage following penetration of armour; however, it fits fairly well with the steel armor equivalences listed being not terribly far from RHAe figures for kinetic penetrators:

Equivalent to 240mm of conventional steel.

Equivalent to 365mm of conventional steel

Due to its STC roots the Rhino can be constructed using locally available materials. Most Rhinos are constructed of a bonded ceramite layer over a cast plasteel hull, although others use carbon composite compounds or conventional hardened steel, depending on their origin.

The inner layer provides the main protection. Its a bonded ceramite/adamantium alloy which provides protection equal to over five times the same width of conventional steel, while being lighter. The second layer is a reinforcing thermoplas with a sub-dermal energy dissipation fibre mesh, providing protection against extremes of heat and radioactivity. The outer layer is a non-magnetic acrylic identification sheath. All in all, this corresponds to over 200mm of conventional steel on the front of the vehicle.

The front armor is 98mm thick, but provides protection equivalent to approximately 300mm of conventional steel.

Actually, there is plenty of evidence of extreme speed governors, which are routinely removed by crews (known in universe as being overcharged) despite being forbidden by regulations.

There's a good amount of inference at them being able to pull modern speeds easily when properly tuned.

That's ignoring all the contradictions in IA itself in the statistics from vehicle to vehicle much less compared to the rest of the universe, as I mentioned before. Which is ironic, as I seem to remember you having problems with a book that you believed to be non reflective of the universe in question.

Incredible something or other?

By all means, present such evidence. In the mean time, I refer you to Azazel's scanned spread, which gives 840 horsepower for a Leman Russ variant (not especially high for a >60 ton tank), and also refer you to the speed of the Imperial Guard's advance on Taros:

After ten days it had made up to one hundred fifty kms; it was behind schedule by between 30 and 50 kms but the broad front was still moving northwards daily.

In the universe, overcharging also has consequences, and supercharged engines rarely used, right? The IA specs are remarkably consistent on speed, as well, strangely. If you want to claim a contradiction with "the rest of the universe," provide evidence for it. The Imperial Guard bogs down. Imperial Armour Vol V describes years of trench warfare on a single static front:

The result was that for long periods of time, sometimes years, the front was entirely static.

Depends really on the type of armor. There have been numerous GJ events, from repeated Hellgun fire to close range plasma detonation.

Lacking are both the incidents and the demonstration that such incidents are GJ range.

Evidence needed.

You don't believe anything I said about BT?

A particle projector cannon's shot puts out a total energy in the e10 joule order of magnitude, and causes significant harm to infantry who happen to be simply near the target. The large laser is not far off from this and similarly causes lethal thermal effects on nearby humans. Even small/medium grade lasers have been observed causing significant destruction in the e9 joule range.

PPC (tens of GJ due to melting glass across the street, significant harm to people):

What cut off her words was a bolt of blue fire hitting the ground in front of the Aung house, the blue fire momentarily blanking Cassie's vision. Through great maroon clouds of afterimage, she saw the big front window shimmer and simple melt away, felt a rush of heat on her face like the hot breath of air when she squatted too near while her mother slid her baking in and out of the oven... In the Aung yard, men were on fire.... The burning men had fallen to the ground. The whole Aung house was ablaze with flames.

Large laser (several GJ per cubic meter of sand):

The single laser he fired missed low, melting a huge glistening
patch of sand into glass before it shattered.

Large laser (multiple infantrymen):

It raised the laser clutched in its right hand and the spotters disappeared in a flash of ruby light.

One heavy laser missed the 'Mech and brushed the running scout like the wings of the Angel of Death. Conteras the truchaseno simply exploded like an insect that had blundered into an electronic bug zapper. Billy Huckaby, the Black hillbilly who was the baby of the platoon, fell down screaming, hair and jacket on fire, polymer armor melting to his flesh...

Medium laser (a few GJ required to match “daisy cutter” through inefficient thermal weapon; incident may be inspired by game-mechanical ability to clear a 15m radius area of wooded terrain using a medium laser in one 10 second turn.)

The impact must have just about driven the MechWarrior's spine out the top of its skull, but he is firing his medium laser and machine guns into the grove even as he hits. Thick boles fly apart in clouds of splinters. Huge leaves wilt in the heat and fray of the bullet-storm. In triumphant fury the Locust lays the stand of trees to waste.

Small laser (minimum several GJ per cubic meter melted):

She swiveled the rear-mounted small laser... The laser’s initial hit caused the encased air and gas that formed the crystal to explode, sending up spears of shrapnel into the Hellbringer’s torso. The laser’s heat also melted the crystal, which flattened beneath the enemy ‘Mech’s supporting foot. .. The Hellbringer slid as the crystals turned to molten rock.

A standard gauss rifle is a 100mm 125kg caliber hypersonic solid slug of some ferromagnetic material with a kinetic energy of 720-1000 megajoules, and enough momentum to cause a BattleMech to skid, plow, or lurch multiple meters. The muzzle velocity of other gauss weapons is similar, although not necessarily exactly the same.

One hypersonic slug missed wide, punching through a building behind the Hauptmann and leaving an impressive wound behind.

The Gauss rifle used a series of magnets to accelerate a nickel-ferrous slug ten centimeters in diameter. The payload burst almost silently from the barrel, but the violent kickback rocked the Caesar back slightly.

Recoil shook the cockpit as the 125-kilogram, magnetically accelerated projectile streaked toward its target, the snap of the sound barrier breaking the only evidence of its discharge.

The Gauss rifle uses a series of magnets to propel a projectile through the rifle barrel toward a target. While it requires a great deal of power to operate, this weapon generates very little heat and can achieve a muzzle velocity twice that of any conventional weapon.

Of course, not even an armored assault vest would withstand the impact of a Zeus sniper's round the size of Cassie's little finger traveling five times the speed of sound.

Note the Compendium refers to any conventional weapon. The highest velocity conventional discarding-sabot rounds are getting quite close to 2 km/s now, and in spite of any loss in technology, at least Mach 5 remains possible for conventional guns in the BT era. Velocity of these rounds is therefore 3400-4000 m/s. This explains the substantial recoil.

The gauss rifle described above will either barely pierce or barely be stopped by a 10 gram/cm^2 layer of BT armor.

The surface area of a 1.7m human is roughly 2 m^2. A 12m BattleMech therefore has roughly 100 square meters of surface area. 10 tons of standard BT armor, distributed in an even layer, gives approximately 15 points per hit location. Accordingly, 10 g/cm^2 is at or near the thickness required to stop a Gauss round (within 10%, accounting for rounding effects).

Armor used on BattleMechs generally exceeds the penetration of modern tank rounds by a comfortable margin.

A piece of steel no thicker than my finger, strengthened by radiation casting techniques and impregnated with a sheet of woven diamond fibers, had stopped cold an armor-piercing shell. That same shell would have gone straight through a third of a meter of normal steel.

“Stopped cold” indicates a comfortable margin.

Based on WorkMechs and the genius of various research groups, the MCK-5S Mackie easily outclassed any weapon that any member-state could put on the field.

There is also the reductio argument thus: BattleMechs rendered conventional tanks of the day, which at worst were similar to modern tanks of the day, completely obsolete. As highly visible targets, this entails being able to take hits from modern tank guns.

Third, see above section regarding gauss rifles. By any measure, the gauss rifle far exceeds modern tank AP rounds; by density of kinetic energy, the dominant factor for high-velocity penetrators, should penetrate close to 10m RHAe.

BattleMechs are quite nimble, and have superior mobility to tanks with similar top speeds.

A blue BattleMaster, Macho Alverado's Macho Man, kicked out one leg on a White Locust, which sent the 'Mech crashing down to the ground. Dark Lady charged up, waving her arms and whistling. Macho tried to crack her in the head with the Fusigon Longtooth extended-range PPC in his 'Mech's right arm. Lady K blocked, then stuck her Atlas' right leg behind Macho Man's ankle, put her right palm against his chest, and dumped the BattleMaster to the ground with a creditable leg-throw and a thump that made Uncle Chandy's teeth knock together with an audible clack.

Show me a tank nimble enough to do judo - or one with the ability to climb sideways on a sheer cliff:

The jagged side of the mountain betrayed her as she stepped to the left along a ninety-degree slope with her Linebacker Prime.

• Powered battle armor mount weapons that are on par with the very lightest weapons used on BattleMechs.
• Most BattleMechs have a rated top speed between 60 and 100 kph. Most tanks also fall in this range.
• BattleTech battle armor and BattleMechs tend to be jump-capable, like Tau crisis suits.

If you're disputing these, I recommend you read unit profiles on Chaos March, a free repository containing all but the most recent "official" BattleMechs and battle armor units.

One heat point in the game from an energy weapon represents on the close order of one gigajoule of waste heat.

A BattleMech is comprised of a number of elements with varying room-temperature capacities - boron nitride (0.6-0.8 J/gK), glasses (0.5-0.9 J/gK), aluminum (0.9 J/gK), steel (0.5 J/gK), assorted plastics, synthetic fibers, and rubbers (0.9-4 J/gK), titanium (0.5 J/gK), nanostructured carbon (0.7-0.9 J/gK), various liquid coolants (2-5 J/gK), air (1 J/gK). Overall, we expect the heat capacity to be fairly close to 1 J/gK at normal operating temperatures.

There is also the harsh environment rule, dictating 1 heat point per ten degrees Celsius. Apply to a 100 ton BattleMech, which will retain the greatest portion of its weapons waste heat: 10K/HP*1J/gK*100,000,000g = 1,000,000,000J/HP.

The high explosive component of BattleTech autocannon shells accounts for the majority of their destructive effect against BattleMechs. The precise explosive mechanism of these uranium-tipped supersonic shells may vary.

Since Gauss rounds are at least twice as fast, they have four times the kinetic energy per unit mass - and yet for the total ammunition weight, including propellant, they only do 1.2 times as much damage. Ergo, the autocannon rounds are not primarily kinetic weapons.

Damage value is in general proportionate to armor shattered (kinetic weapons) melted/vaporized (thermal weapons), or a combination of the two (explosive weapons).

The Com Guard MechWarrior stayed with his 'Mech long enough for Jez's Warhawk to shred two tons of his armor in a wracking series of laser blasts doled out at devastating range.

They missed a fast lance of Scarabus designs that bolted for the backside at better than one hundred kilometers per hour. Only two survived to take a swing at Victor's Daishi. One missed. The other carved away a half ton of armor from Prometheus's arm.

Peter squeezed out another gauss rifle shot, more from reflex than deliberation. The mass struck Nondi's OmniMech in the left leg this time, smashing enough armor to build a small tank.

Grinding his teeth in defiance, Rudolf Shakov divided his fire between the Nigh Hawk and whenever he could get a targeting lock, the Barghest.A laser brightened the armor over his left leg, carrying off a half-ton of his protective shell.

In general proportionate to mechanical damage values, to the point where they are worth talking about? Yes.

Going to need to see proof of all of this. You especially need to prove that the game data matches the universe and back up any calcs with fluff.

Every bit of this section follows from the above three sections logically. You need to dispute the above in order to successfully dispute these conclusions. For example, a gauss rifle penetrates something like 10 meters RHAe, while the Land Raider's equivalence to 300-365mm of "conventional steel armor" is not going to be too terribly far from equivalent thicknesses of RHA.

And this. Especially since Imperial Guard vehicles have withstood the same thing on their side armor.

Re-laying the gun took a vital second. In that time, the second tank fired again and hit the Wrath squarely. The impact was enough to lurch all sixty-two tonnes of armoured machine several metres sideways. But it didn't penetrate the twenty centimetre-thick armour skin.

(Please indicate the source of your quote when quoting.)
Lurching several meters sideways on a hill does not mean the attack is anywhere near the power of a gauss rifle. Try again.

Again with the proof needed.

Such is demonstrated by its superior effect vs BattleMechs (as opposed to modern tank weapons) and the near-parity of Battle Cannon with modern tank weapons.

Ignoring the bits about speed I commented on before: I have no clue where you got the idea it turned slowly. It can also go through far higher than meter deep mud since its got a great deal of torque among other features, such as legendary reliability.

Slow turning (relative to BattleMechs) is an inevitable consequence of having a top off-road speed of 21 kph. You're not turning treads quickly.

MAXIMUM SPEED: 34 kph on road, 24 kph off road
FORDING DEPTH: 1.9m
GROUND CLEARANCE: 0.45m

A BattleMech does not have a "fording depth" because it can be fully immersed. Please, evidence for maneuverability and terrain handling.

You are also incorrectly referencing the Conquerer part of IA: It was found that it had better accuracy on the move because it had a better stabilizer.

No, IA states that it is because of the reduced recoil:

The reduced recoil allows the vehicle to fire whilst on the move, making this Leman Russ variant more mobile when leading an assault.

The description of the arch-enemies knock off Leman Russ and how it relates to the Conqueror

LeGuin had it right. Examples of old, sub-Imperial standard technology, the Reavers lacked any auspex guidance or laser rangefinding. It was also clear they had no gyro stabilizers. Once the Conqueror guns were aimed they damn well stayed aim-locked thanks to inertial dampers, no matter how much bouncing and lurching the tank was experiencing. That meant the Conquerors could shoot and move simultaneously without any appreciable loss of target lock. The AT70s fired by eye and any movement or jarring required immediate aim revision.

All that quote does is establish that Conquerors do fire pretty well on the move.

Unfortunately its also a mech, with all the tremendous flaws that come along with that.

"All" meaning visibility and surface area. Unfortunately for WH40K, it faces the same problem that pre-BattleMech era tanks faced in the BT universe: They have magic-nano armor that seemingly violates physics.

Here's a hint: Its going to suck at everything you think its going to be good at. Oh I'm sure its probably done some of those in fluff, but in any realistic environment its boned.

In other words, you're sure it canonically, in the BT universe, is able to maneuver very well and deal with all sorts of obstacles, but are unwilling to suspend your disbelief regarding its maneuverability, because of pre-existing bias against giant humanoid war machines.

I'm sorry, but in order to deal plausibly with the BT universe, you're going to have to accept that BattleMechs actually can do the things they're described as doing in BT.

Requiring multiple hits to kill is actually standard for the Leman Russ.
A couple examples:

An AT70 lobbed a shell at the Wild One that tore away its sponson and part of its track skirt. Another hit the Demands With Menaces on the turret destroying its vox-mast, pintle mount and laser range-finder, and killing the assistant gunner with explosive spalling.

Wounded but not down, the Demands With Menaces plunged forward, laying its guns at the Reaver responsible. Corbec saw the top-hatch pop and the commander emerge, oblivious to the danger, to verify aim with a handscope now his range-finder was

Emboldened by the sight of a Leman Russ burning, the Brigand stirred forward again, and hammered a shot at the Access Denied that crushed its front bracings and fore-hull plating.

Both examples involving immediate damage impacting the combat effectiveness of the tank. Perhaps several hits to actually destroy is typical:

The 15th Tank company, consisting of a dozen Leman Russes was commanded by Captain Gerszon from his own Vanquisher... It wasn't long before he spotted enemy tanks to the south. Opening fire at long range he scored a hit, and a cloud of black smoke rose from his target.

One hit.

The enemy pressed forward, and armour-piercing tank shells were flying back and forth. One shell glanced off Gerszon's turret, another disabled the bow lascannon, leaving the gunner mortally wounded. Gerszon hit two more enemy tanks before being struck for a third time. This time a fuel tank ruptured.

Three hits.

One Land Raider was still moving, and its nearest lascannon swiveled towards them, a moment later a bolt of laser energy spat out of the dust, tearing through the turret of one of the Executioners.

Lascannon blast goes straight through the turret armor of an Executioner variant Leman Russ.

"Fire!" he called and Old Relentless roared its fury, wreathing Vorto in a pall of dissipating smoke so that he couldn't see if the hit was good or not. "And again!" he shouted... "One more for the Emperor!" he urged Braganzi on, watching as a stab of laser from a Destroyer punched through the side sponson of a Chaos Predator... Plasma spewed onto the sand, fusing it into glass, the shot obviously having breached the Land Raider's internal reactor.

Laser Destroyer goes through Predator side armor. Also, 2-3 shots from a Vanquisher to kill a Land Raider.

There's also a volume of examples in Honour Guard where concentrated fire is required to take down a Russ. That includes main gun and lascannon fire.

I eagerly await it.

That's because its own weapons are underwhelming for the weight class its in.

They may be underwhelming for its own weight class in BT, but they are quite overwhelming for its weight class in WH40K. Note that its armor is also not fantastic by BT standards. This is an older model Dragon, appropriate to compare to the stock model Leman Russ.

Clearly goes in the Leman Russ' favor if you know anything about ground combat.

Does it? As far as control goes, a BattleMech basically fights like one giant AI-assisted infantryman; as far as logistics goes, the dramatically reduced logistics requirements of BT forces is one of their big advantages.

[Thanatos]

Hence why I said only qualitative information held, and only within a given army

Actually, it doesn't even match up within an army. For example, infantry autocannons have the same stats save range as the long barrel quad guns on the Hydra, despite the Hydra using far more powerful cannons. You'll see that on all the weapons within a class. There's a wide range of weapons where they're given a universal stat despite their vast differences.

I would be quite a bit off. The Space Marines' bolter, however, is a larger and more powerful weapon, and fires high-explosive shells.

Sorry about that, I was off by a single decimal place when looking at your response and thought you were saying single to double digit KJ. Which is part of why I requested you to not mix notation.

As indicated here, a WWII-era 134mm naval gun used by the British, firing a 36.3 kg shell at 792 m/s, had a range of 21 kilometers.

You used a naval gun? That's a bit dishonest when you say the Earthshaker has WW2 performance, since that implies WW2 field guns.

The 15-16 km range figure is repeated in Imperial Armour volumes I, III, and V, in narration as well as fluff text.

I would hope so, its written by the same guy. However, we have multiple sources that contradict this. Necropolis has plunging Earthshaker fire well past 70km and Tactica Imperialis has 100km Earthshaker fire.

It also means the force on the bullet and the barrel itself are being applied over a shorter distance; the Conqueror barrel is 2.49m (Imperial Armour) while the Abrams barrel, a sample modern tank barrel, is 9.77m.

Horrendously wrong on the Abrams barrel. The L44 is 5.28m and the L55 is 6.6m. The Abrams' M256 is the L44, so you're off by more than four meters.

190T*2.49m=473T*m; 56T*9.77m=548.8T*m - that's 16% more energy.

Also incredibly wrong, its the weight of the gun not the length of the barrel that determines recoil velocity and force.

Barrel length effects the dyamics of the round and adds additional weight as a side effect, reducing recoil. While we know the total weight of the M256, we don't know the weight of the

Furthermore, the above citations make it clear that the Earthshaker operates at close to the maximum recoil of the Chimera chassis, which also constrains the force of WH40K tank guns.

No your quote says that

Basilisks do not use overcharging, as the Chimera chassis is not considered stable enough, making shots wildly inaccurate.

Considering that the Earthshaker weighs almost as much as the chassis its on, its not exactly surprising.

Blowing man-sized holes in walls is within the capabilities of modern MBT guns.

Note that it doesn't say "Man sized". Note that it doesn't specify the size of the whole, note that it doesn't specify the building materials, note that it doesn't give us any comparison points at all.

Assuming the Conqueror manages to apply a peak 190 tonne force for the whole 2.49m length of its barrel, it has a muzzle energy of 4.6 megajoules.

Again, wrong. Its weight not length that determines recoil force.

Also note that even the 155m shell you described has a muzzle energy of 6.1 megajoules

The muzzle energy of an M829A3 out of an L44 is 12MJ.

My calculations were that if lascannons could perform a feat I have never seen them perform, then they could have a yield of that much.

Again, where are you getting this from? You haven't clarified what you have used to initially come up with 2GJ.

We see no such collateral damage in the game

Stop using the game! How many times and in how many ways do I have to tell you that?

And when have you seen Lascannon impacts that have failed to live up to what you think weapons of that power should do?

Not secondary, total effects

Actually no, to flash burn or sear those not caught outside the beam requires high MJ range energy since you need to superheat the air to the point that it can cause searing or burning.

Guarantee? Of course not. Strong possibility? Thus speaks the fluff:

You can penetrate an Abrams with lighter weapons and a lot of luck if you aim at the right place on the hull. Examples of tanks being destroyed by Lascannon fire does not tell us its penetration or first "round" kill probablility. We know it can penetrate tank armor but we don't how well it does it. We have examples of tanks taking repeated Lascannon fire without being penetrated.

For example, one in Honour Guard.

The disarmed Infardi machine was closing to less than forty metres now, and its hull-mounted lascannon began to spit bolts

of blue light at Sirius' conqueror.
..
With furious las-fire from the injured tank now splashing off the Wrath of Pardua's front casing, Sirus ordered his

layer to address the other tank coming around the first.

As for the example from Inferno, it depends on how you define an hour of combat. An Abrams with a loader at the maximum allowed loading time can empty its ready racks in under two minutes and a good loader can get that down to a minute. However, maximum rate of properly ranged fire is limited by the fact that using the LRF that much in that space of time will burn it out, leaving you fucked. That's just the ready racks, you have to transfer rounds into them from the other ammo compartments after that.

There are a ton of variables that can go into determining "combat time" and we don't know any off them.

We do have an example of vehicle Lascannon ammo capacity with the Lightning and Thunderbolt having 30 Lascannon shots across two packs or 15 shots per gun. This is thanks to them lacking the ability to charge their packs like a vehicle. So, if you assume that they use the same packs (since the Lascannons and their packs are to my knowledge the same as those mounted on a tank) that gives you 1.8GJ to 2.8GJ. 15 shots in one hour of "combat" is about right really since that's what a tank can expect to fire out of its main gun in an hour unless its in particularly heavy fighting.

However, it is important to remember that it is old fluff and a lot of the other values listed have changed.

Most generous interpretation: 28 MJ/shot * 200 shots = 5.6 GJ. Considering the man-portable scale of the lascannon, and the size of the power pack displayed on the Space Marine-portable variant, I expect at least three shots per infantryman's-backpack of power pack.

They don't use the same packs. The infantry lascannon pack is much larger than the Krieg's Hellgun powerpack as you can see by these comparitive photos.
Hellgun pack on the right. Krieg hellguns appear to be missing the generator found on Kasrkin hellguns.

And this is a good comparitive shot of a Lascannon pack.

Much, much larger. Ammo capacity on Lascannon packs is listed as being anywhere from 1-5 rounds.

Tau railguns, however, seem in particular effective:

Yes, they're the second best tank killing weapon in 40K, the first being the Vanquisher. You should note that the Tiger Shark X10 uses much heavier railguns than a Hammerhead. They're pulled off off a Manta and are titan killer grade weapons.

PPC (tens of GJ due to melting glass across the street, significant harm to people):

No evidence of the glass being across the street given no description of the terrain. People on fire not surprising given that its a plasma weapon but no real evidence of any high firepower.

Large laser (several GJ per cubic meter of sand):

No size given or depth of sand glassed. No evidence of glassing in the cubic meter range. Too subjective to be of use.

Large laser (multiple infantrymen):

Disappearing is too vague to be used for to calculate effects.

Medium laser (a few GJ required to match “daisy cutter” through inefficient thermal weapon; incident may be inspired by game-mechanical ability to clear a 15m radius area of wooded terrain using a medium laser in one 10 second turn.)

Statement conveniently ignores MG fire but not its effects. Utterly dishonest.

Small laser (minimum several GJ per cubic meter melted):

No amount of material mentioned and reference to exploding gas undercuts reliability of using it. Like claiming a match is a kiloton weapon based on the PEPCON explosion.

This isn't exactly blowing my skirt up thus far.

Oh and actual evidence for Gauss Guns? Wow, did it hurt actually bringing actual evidence in for once? Given your reluctance to actually do that in every thread ever, I though you might have an allergy to it or something. ;)

There is also the reductio argument thus: BattleMechs rendered conventional tanks of the day, which at worst were similar to modern tanks of the day, completely obsolete.

Out of universe argument. Stick to the weapons themselves.

Show me a tank nimble enough to do judo

Why would you want to? Oh and I see that you were being a hypocrite when you claimed that 40K had short ranges based on HTH events.

Overall, we expect the heat capacity to be fairly close to 1 J/gK at normal operating temperatures.

No proof given at all of course.

In general proportionate to mechanical damage values, to the point where they are worth talking about?

Except that you have nothing proving the connection between them. Heck, you didn't even try. You didn't show that the effect matched the weapon stat in the slightest among other things.

For example, a gauss rifle penetrates something like 10 meters RHAe

Wow, "Something like". Very technical term backed up by, well, nothing. Where did

Lurching several meters sideways on a hill does not mean the attack is anywhere near the power of a gauss rifle.

First off, there was no hill. Secondly, you used a 100 ton mech getting staggered as evidence of Gauss gun power. A 60 ton tank being shoved sideways is a higher level event since it has more resistance to movement on the ground and there's no stumbling effect.

And it should be noted that there is no way for modern armor to survive that.

No, IA states that it is because of the reduced recoil:

Which IA is that from? IA1 states in the flavor text on that it has better performance on the move than a standard Russ.

Furthermore, saying a Leman Russ can't fire on the move contradicts at least a dozen sources. Necropolis, Honour Guard, Death or Glory, His Last Command, etc

All that quote does is establish that Conquerors do fire pretty well on the move.

Way to totally miss the comparison to the standard Leman Russ in both quotes.

The Imperial Guard bogs down. Imperial Armour Vol V describes years of trench warfare on a single static front:

You're leaving out any context:

Since its first construction it had always been known that the Citadel and star port on Vraks would be vulnerable to an orbital assault. The defences had been deisgned to repulse just such an attack. Batteries of planetary defencee lasers ringed them, maybe as many as a hundred operational guns. There was enough firepower on the surface of Vraks to fight an entire fleet in low orbit. The Imperial Navy's battleship sand cruisers were hugely powerful starships, but no ship can fight a planet. With batteries buried deep to withstand orbital bombardment, the ships would be at a massive disadvantage in a straight fight. to land troops the ships would need to approach in low orbit and they would be vulenrable
as they manoeuvred into position to launc their landing ships. The landing ships themselves would be targeted, and a single hit from a defence laser would tear a landing craft apart. Below the defence lasers was a network of high and low altitude anti-aircraft defences that could engage any craft that got through. The conclusion drawn from the Logis' calculations was that the risk of a direct attack was too great. The probability was high that a planetary assault would be repulsed with great loss."

Within the Departmento Munitorum it is now believed that Vraks is an impregnable fortress. Its walls are protected from orbital bombardment by void shield generators. It has an extensive curtain wall protecting it from direct assault. It is surrounded by a large network of defence laser batteries, making an assault from orbit suicidal for any star
ship. These lasers can also be used against ground targets, and all approaches to the Citadel are covered by interlocking fields of fire. Three defence rings run from miles out into the wastes. These protect the storage bunkers from raiders and include trenches, defence lines, bunkers and strong points as well as pre-prepared artillery positions. The defence lines are further protected by lines of razorwire, tank traps and thousands of minefields

Vraks was going to be such a bloody, attrition warfare style battle for the Guard that they had to turn to their attrition warfare specialists, the Death Korps of Krieg. Not only are the Krieg crazy enough for it, but they're one of the only regiments dedicated to it. The fact that even they got bogged down shows its a horrendously brutal war.

Hell, when the Dark Angels decided to help, albeit for selfish reasons because they're dicks, they lost over 200 battlebrothers in fighting behind enemy lines.

also refer you to the speed of the Imperial Guard's advance on Taros:

You are confusing rate of advance with vehicle speed. You're also leaving out all the information regarding battles, watching for ambushes, air attacks, etc. They were only advancing 15km a day because the Tau were making it impossible to go any faster.
For comparison: The US invasion of Iraq in 2003 only advanced at a rate of 35km a day on average and it was the fastest invasion ever. Luckily, they didn't have to deal with a foe at the level of the Tau.

One hit.

You'll note its a Vanquisher, which I explicitly said had the best first round kill chances.

Lascannon blast goes straight through the turret armor of an Executioner variant Leman Russ.

Land Raider Lascannons are more powerful than their counterparts. Another internally inconsistent bit if you insisted on using the non-canonical rules.

By all means, present such evidence.

For starters, the Chimera has a top speed of 70km\s and the stripped down Trojan has a top speed of 80km\s despite being less than a 10th the weight. Furthermore, the Rhino series can perform at 100% on 50% power and can take additional weight with ease.

Among other things such as high speed scissoring thunder runs by armor in Necropolis, cautious advances at a speed of at least 50kph in Honour Guard and numerous other examples.

The AdMech treasures century after century reliability (literally), so them governing it more harshly than modern tanks makes sense from their point of view. Its the age old battle between us and the mechs. The mechs never want you to do anything fun. :p

As for the effect of overcharging, yeah it increases strain and wear on the engine and suspension. So does going fast or doing hard manuevers in a modern tank. Hell, pretty much every moving part on a tank will fail eventually. I've had a drivers hatch fail to open for me on the same day my CVC helmet mic gave out and another tank snapped a track plowing it several feet into the ground during a sagger dril.

The AdMech is just overzealous about preventative measures. Its part of their character along with tech hoarding. Vehicle crews just happen to be luckier than most and can actually work on their own stuff without much AdMech interference.

A relatively primitive version of the modern discarding-sabot round.

That's basically the exact definition of a modern Sabot.

Slow turning (relative to BattleMechs) is an inevitable consequence of having a top off-road speed of 21 kph. You're not turning treads quickly

Turning speed\radius is not a direct function of road speed except for the fact that turning radius increases with speed.

A piece of steel no thicker than my finger, strengthened by radiation casting techniques and impregnated with a sheet of woven diamond fibers, had stopped cold an armor-piercing shell

Remember: Its only modern conventional steel if its 40K.

The Rhino is usually constructed with plasteel... but can be constructed using conventional hardened steel.

Except for the fact that its all over the place as it mentions standard plasteel construction and you're basically just quoting the same thing over and over again from the same source. I'm still compiling my stuff, but let me leave you with this question: Why is it that you assume its modern RHA without any evidence? What evidence do you have that its modern steel? Why does the steel based battletech armor get a pass from you but you automatically assume the worst for 40K, in defiance of all other evidence? Modern steel can't withstand the kind of impact that would shove a 62 ton vehicle several meters sideways.

Hell, an Abrams can't even withstand that much energy by far. A mega IED is enough to utterly mission kill an Abrams, warp the hull beyond repair and transmit enough of the shock into the tank to break bones. The fact that we see none of this on a tank victim to far more energy is telling. The crew all survived with no serious injury and had the tank back at 100% in under an hour.

That's about all I have time for right now.

[Jedi Master Spock]

Actually, it doesn't even match up within an army. For example, infantry autocannons have the same stats save range as the long barrel quad guns on the Hydra, despite the Hydra using far more powerful cannons. You'll see that on all the weapons within a class. There's a wide range of weapons where they're given a universal stat despite their vast differences.

Ahh, but are not all of those autocannons more powerful than a heavy bolter and less powerful than a battle cannon - per salvo, anyway? That's all I'm asserting here.

Sorry about that, I was off by a single decimal place when looking at your response and thought you were saying single to double digit KJ. Which is part of why I requested you to not mix notation.

I will take this as agreement, then.

You used a naval gun? That's a bit dishonest when you say the Earthshaker has WW2 performance, since that implies WW2 field guns.

Naval guns were fielded in fixed emplacements as well; the Basilisk's 9m barrel does put it rather larger than most infantry-towed field guns.

I would hope so, its written by the same guy. However, we have multiple sources that contradict this. Necropolis has plunging Earthshaker fire well past 70km and Tactica Imperialis has 100km Earthshaker fire.

Exact quotes, please. The Imperial Armour books are quite recent (Vol V came out just last December) and, I would presume, were subject to at least as much editorial oversight as the novels. More specifically, they contain what amount to novellas of WH40k fiction within them; this material is not just "game mechanics window dressing," but also "fiction fluff."

It also means the force on the bullet and the barrel itself are being applied over a shorter distance; the Conqueror barrel is 2.49m (Imperial Armour) while the Abrams barrel, a sample modern tank barrel, is 9.77m.

Horrendously wrong on the Abrams barrel. The L44 is 5.28m and the L55 is 6.6m. The Abrams' M256 is the L44, so you're off by more than four meters.

I stand corrected.

Also incredibly wrong, its the weight of the gun not the length of the barrel that determines recoil velocity and force.

The mass of the recoiling assembly determines the recoil velocity of the assembly, which determines the energy required to stop it (force over distance).

The recoil force backwards on the recoiling assembly is the same as the forward force on the bullet, as is the total change in momentum. The muzzle energy of the gun is the force (dot) the distance traveled by the bullet.

Now, what you're talking about is the force of the gun on the tank, but these are generally proportionate, because gun mass is linearly proportionate to gun length in much the same manner.

Barrel length effects the dyamics of the round and adds additional weight as a side effect, reducing recoil. While we know the total weight of the M256, we don't know the weight of the

True; however, we do know that the Earthshaker, with its massive 9m barrel, is bigger than the tank guns; thus, it will have a better ratio of recoil energy to muzzle energy, and will have less recoil force for the same shell.

So if any of the tank guns fires an equivalent shell, it will have more recoil.

No your quote says that

Basilisks do not use overcharging, as the Chimera chassis is not considered stable enough, making shots wildly inaccurate.

Considering that the Earthshaker weighs almost as much as the chassis its on, its not exactly surprising.

Fired using the standard 5 charges, an enclosed Basilisk cannot use the larger charges 6 and 7, due the recoil restriction of the fighting compartment.

Recoil restriction of the fighting compartment, meaning that if it were more powerful, it would require more recoil distance than is available or more force than the chassis can handle. Any more recoil energy would be a problem.

Note that it doesn't say "Man sized". Note that it doesn't specify the size of the whole, note that it doesn't specify the building materials, note that it doesn't give us any comparison points at all.

Sure it does. It's a hole in the wall that marines rush through.

Again, wrong. Its weight not length that determines recoil force.

Length times force gives muzzle energy. I was talking about the force between the gun and bullet; you have been talking about the force between the gun and the tank. The case I described was basically the case where the entire tank is one large rigid recoiling assembly.

The muzzle energy of an M829A3 out of an L44 is 12MJ.

Almost precisely equal to the Earthshaker.

My calculations were that if lascannons could perform a feat I have never seen them perform, then they could have a yield of that much.

Again, where are you getting this from? You haven't clarified what you have used to initially come up with 2GJ.

I already gave three reasons.

We see no such collateral damage in the game

Stop using the game! How many times and in how many ways do I have to tell you that?

And when have you seen Lascannon impacts that have failed to live up to what you think weapons of that power should do?

Not secondary, total effects

Actually no, to flash burn or sear those not caught outside the beam requires high MJ range energy since you need to superheat the air to the point that it can cause searing or burning.

High MJ. Not gigajoule. If you have high MJ energy, you can start causing substantial collateral damage; with multiple gigajoules, it becomes unavoidable. I further present:

A medium-magnitude laser is discharged into a massive crystal that greatly amplifies the potency of the shot in a fraction of a second. This energy can be discharged in a focused beam capable of blasting through the thickest armour, or dispersed to slay entire squads of infantry.

A laser weapon similarly capable of piercing the "thickest armor" - but does not ordinarily threaten squads of infantry, unless fired on a special "dispersed" setting. It may be more or less powerful than the lascannon, but it is clearly also a laser weapon capable of piercing WH40k tank armor, and also clearly not more than the 2 gigajoule line I set earlier.

You can penetrate an Abrams with lighter weapons and a lot of luck if you aim at the right place on the hull. Examples of tanks being destroyed by Lascannon fire does not tell us its penetration or first "round" kill probablility. We know it can penetrate tank armor but we don't how well it does it. We have examples of tanks taking repeated Lascannon fire without being penetrated.

And we have examples with only a couple shots, which I have quoted previously, and we have the stated ability to penetrate.

I assume that lascannon barely pierce Land Raider armor; you need to hit at a good angle with little relative motion between you and the Land Raider. Adding relative motion, or tilting the angle, increases the area of armor you must penetrate.

For example, one in Honour Guard.

The disarmed Infardi machine was closing to less than forty metres now, and its hull-mounted lascannon began to spit bolts of blue light at Sirius' conqueror... With furious las-fire from the injured tank now splashing off the Wrath of Pardua's front casing, Sirus ordered his layer to address the other tank coming around the first.

As for the example from Inferno, it depends on how you define an hour of combat. An Abrams with a loader at the maximum allowed loading time can empty its ready racks in under two minutes and a good loader can get that down to a minute. However, maximum rate of properly ranged fire is limited by the fact that using the LRF that much in that space of time will burn it out, leaving you fucked. That's just the ready racks, you have to transfer rounds into them from the other ammo compartments after that. There are a ton of variables that can go into determining "combat time" and we don't know any off them.

We do have an example of vehicle Lascannon ammo capacity with the Lightning and Thunderbolt having 30 Lascannon shots across two packs or 15 shots per gun. This is thanks to them lacking the ability to charge their packs like a vehicle. So, if you assume that they use the same packs (since the Lascannons and their packs are to my knowledge the same as those mounted on a tank) that gives you 1.8GJ to 2.8GJ. 15 shots in one hour of "combat" is about right really since that's what a tank can expect to fire out of its main gun in an hour unless its in particularly heavy fighting.

However, it is important to remember that it is old fluff and a lot of the other values listed have changed.

And that's power consumption. 15 shots is probably on the low end, since that's the lowest shot capacity given for any lascannon units others have 20 or more. These are present in Imperial Armour Vol I-II, which are basically current techmanuals. The Vol I-V numbered series were published from 10/2003-12/2007, and ForgeWorld is still selling them on their website.

They don't use the same packs. The infantry lascannon pack is much larger than the Krieg's Hellgun powerpack as you can see by these comparitive photos.
Hellgun pack on the right. Krieg hellguns appear to be missing the generator found on Kasrkin hellguns.

And this is a good comparitive shot of a Lascannon pack.

Much, much larger.

Not actually that much. Note the lascannon troopers carry smaller backpacks. That lascannon power pack is no more than about double the size. This, when effective yield of las weapons seems to be at roughly the ratio of 2 megajoules for 19 megathules. We're still nowhere near justifying >2 GJ effect.

Ammo capacity on Lascannon packs is listed as being anywhere from 1-5 rounds.

Source?

Now, I have presented my case for lascannon being no more than 2 gigajoules in actual effect; you have expressed your concerns about it. Do you have any positive evidence to present regarding the yield of lascannons to establish them as being more than 2 gigajoules?

Yes, they're the second best tank killing weapon in 40K, the first being the Vanquisher. You should note that the Tiger Shark X10 uses much heavier railguns than a Hammerhead. They're pulled off off a Manta and are titan killer grade weapons.

I'm aware. I'm also aware the Tiger Shark is still only 25 tons.

No evidence of the glass being across the street given no description of the terrain.

Please review the quote. Cassie is looking through the front window at another house (the Aungs', not her family's) - the front of a house is the side facing the street. Ergo, the strike is across the street.

People on fire not surprising given that its a plasma weapon but no real evidence of any high firepower.

Actually, it is very real evidence of high firepower (as is instantly setting the entire front of the Aung house on fire), and the sort of incident we don't see in Warhammer, to my knowledge. The glass melting across the street is more impressive, though; when we factor in that, it's difficult to keep below a hundred gigajoules. If 100% of the energy is distributed radially, and 100% is absorbed by 4mm of 2.5 g/cc plate glass (both questionable underestimates), which gets 1000 J/g (just short of a proper liquification, but enough to soften it a lot), we have 10,000,000 J/m^2 on, if the distance is 10m (about right for the front yard of a house on the other side of an avenue), a 314 square meter sphere, or 30 gigajoules.

That's the first order of approximation. It adjusts upwards a little bit as we take other factors into account, such as energy wasted vaporizing/melting dirt and grass in the Aung's yard, heating of the air, et cetera.

No size given or depth of sand glassed. No evidence of glassing in the cubic meter range. Too subjective to be of use.

Size is enough to be easily visible from a high speed strafing fighter a good distance away - and also to shatter immediately as it cools. Ergo, most likely multiple cubic meters.

Disappearing is too vague to be used for to calculate effects.

Both incidents clearly killed two people each. Both do not establish a precise yield; it does establish collateral damage. The graphic vaporization in Close Quarters places the yield well above that necessary to vaporize a human, however, and melting kevlar at a distance does suggest ~ GJ range energy was released in the bug-zapper incident.

Medium laser (a few GJ required to match “daisy cutter” through inefficient thermal weapon; incident may be inspired by game-mechanical ability to clear a 15m radius area of wooded terrain using a medium laser in one 10 second turn.)

Statement conveniently ignores MG fire but not its effects. Utterly dishonest.

MG fire has limited effects, and is far less energetic. The medium laser clearly did most of the work.

Small laser (minimum several GJ per cubic meter melted):

No amount of material mentioned and reference to exploding gas undercuts reliability of using it. Like claiming a match is a kiloton weapon based on the PEPCON explosion.

The amount of molten material present is sufficient to cause a BattleMech to slip. If we're proportionately talking about something the size of a banana peel, it's more than a gigajoule.

Oh and actual evidence for Gauss Guns?

You just ignored a series of five quotes, which rather precisely established my claims.

One hypersonic slug missed wide, punching through a building behind the Hauptmann and leaving an impressive wound behind.

Hypersonic slug goes through a building of similar size to a BattleMech, i.e., a substantial office building of some sort.

The Gauss rifle used a series of magnets to accelerate a nickel-ferrous slug ten centimeters in diameter. The payload burst almost silently from the barrel, but the violent kickback rocked the Caesar back slightly.

The recoil I mentioned; also the caliber.

Recoil shook the cockpit as the 125-kilogram, magnetically accelerated projectile streaked toward its target, the snap of the sound barrier breaking the only evidence of its discharge.

Establishes the mass of the projectile.

The Gauss rifle uses a series of magnets to propel a projectile through the rifle barrel toward a target. While it requires a great deal of power to operate, this weapon generates very little heat and can achieve a muzzle velocity twice that of any conventional weapon.

Conventional guns of today almost reach 2,000 m/s. Could easily be 4,000 m/s for the GR.

Of course, not even an armored assault vest would withstand the impact of a Zeus sniper's round the size of Cassie's little finger traveling five times the speed of sound.

The Zeus sniper rifle is a conventional weapon. Minimum of Mach 10 velocity for the GR - 3,400 m/s.

Out of universe argument. Stick to the weapons themselves.

Argument in accordance with the principles stated above - one you did not challenge. Both WH40k and BT have our own past in common with their own. BT in particular is concerned with 20th century military technology in its fluff. Further, this is explicitly stated in BT material:

Although the technology level among the Successor States has fallen since the days of the Star League, it is generally accepted that weapons technology during the 31st century is still at or above the levels common in the late 20th/early 21st century.

Why would you want to? Oh and I see that you were being a hypocrite when you claimed that 40K had short ranges based on HTH events.

I stated we were unlikely to establish any real difference in effective range between the two. I have not yet, in this debate, been concerned with range.

No proof given at all of course.

Except the long list of specific heat capacities of materials (almost all of which increase with temperature), which is all the evidence that is needed to establish the ballpark beyond any reasonable doubt. Objection dismissed.

Except that you have nothing proving the connection between them. Heck, you didn't even try. You didn't show that the effect matched the weapon stat in the slightest among other things.

You are welcome to compare those incidents. I will go as far as to mention that standard armor has 16 points per ton. One half ton is therefore eight points, corresponding to one Inner Sphere large laser hit. You may be able to examine those incidents in that light; I trust that if you do, you will come to the conclusion that a large laser melting a half ton is precisely in line with game mechanics.

Wow, "Something like". Very technical term backed up by, well, nothing. Where did

I recommend you read Nathan Okun's treatise on armor penetration. In general, all armors are pretty "soft" at hypersonic velocities, and so the best approximation to use is k~1, penetration proportionate to density of kinetic energy.

This was a solid steel penetrator; at a final velocity of ~1500 m/s, the 3.6 kg 41mm caliber penetrator would penetrate 245mm of steel. The 125 kg 100mm caliber 3400-4000 m/s penetrator will penetrate 7-10m of steel.

First off, there was no hill.

Connor McLeod says otherwise in discussing the incident.

Secondly, you used a 100 ton mech getting staggered as evidence of Gauss gun power. A 60 ton tank being shoved sideways is a higher level event since it has more resistance to movement on the ground and there's no stumbling effect.

No "stumbling effect" means a shorter distance. Sideways also means on the axis of least resistance for the treads vs multi-meganewton legs, hips, etc. We can account for an additional two orders of magnitude in the BattleMech example through increased force of resistance and increased distance that force is applied over.

And it should be noted that there is no way for modern armor to survive that.

We already have a measure of the momentum associated with the shells themselves, and the logical conclusion is that the lurching is not from the kinetic impact of the shell, but from the much more powerful high explosives it contains. Honour Guard is the same source that gives such a high bursting charge for the Earthshaker.

Which IA is that from? IA1 states in the flavor text on that it has better performance on the move than a standard Russ.

The first one (not Volume I, the older one just called "Imperial Armour"). It says reduced recoil is the reason why the accuracy is better on the move, exactly as quoted.

Furthermore, saying a Leman Russ can't fire on the move contradicts at least a dozen sources. Necropolis, Honour Guard, Death or Glory, His Last Command, etc

It's not that it can't fire on the move; it's that it isn't especially good at it.

Way to totally miss the comparison to the standard Leman Russ in both quotes.

Namely, "Conqueror much better at this."

You're leaving out any context:

Since its first construction it had always been known that the Citadel and star port on Vraks would be vulnerable to an orbital assault. The defences had been deisgned to repulse just such an attack. Batteries of planetary defencee lasers ringed them, maybe as many as a hundred operational guns. There was enough firepower on the surface of Vraks to fight an entire fleet in low orbit. The Imperial Navy's battleship sand cruisers were hugely powerful starships, but no ship can fight a planet. With batteries buried deep to withstand orbital bombardment, the ships would be at a massive disadvantage in a straight fight. to land troops the ships would need to approach in low orbit and they would be vulenrable as they manoeuvred into position to launc their landing ships. The landing ships themselves would be targeted, and a single hit from a defence laser would tear a landing craft apart. Below the defence lasers was a network of high and low altitude anti-aircraft defences that could engage any craft that got through. The conclusion drawn from the Logis' calculations was that the risk of a direct attack was too great. The probability was high that a planetary assault would be repulsed with great loss."

Within the Departmento Munitorum it is now believed that Vraks is an impregnable fortress. Its walls are protected from orbital bombardment by void shield generators. It has an extensive curtain wall protecting it from direct assault. It is surrounded by a large network of defence laser batteries, making an assault from orbit suicidal for any star ship. These lasers can also be used against ground targets, and all approaches to the Citadel are covered by interlocking fields of fire. Three defence rings run from miles out into the wastes. These protect the storage bunkers from raiders and include trenches, defence lines, bunkers and strong points as well as pre-prepared artillery positions. The defence lines are further protected by lines of razorwire, tank traps and thousands of minefields

Vraks was going to be such a bloody, attrition warfare style battle for the Guard that they had to turn to their attrition warfare specialists, the Death Korps of Krieg. Not only are the Krieg crazy enough for it, but they're one of the only regiments dedicated to it. The fact that even they got bogged down shows its a horrendously brutal war.

Hell, when the Dark Angels decided to help, albeit for selfish reasons because they're dicks, they lost over 200 battlebrothers in fighting behind enemy lines.

The outer trenches were not protected by shields. Nor is the orbital fire particularly accurate:

On occasion those same ships may be called upon to make more limited strikes in the hopes of destroying nests of corruption or extremely powerful adversaries. This is often extremely dangerous for friendly forces in the area as the strike is far from pinpoint accurate.

Nor is it simply orbital fire which led to trench warfare being considered obsolete.

You are confusing rate of advance with vehicle speed. You're also leaving out all the information regarding battles, watching for ambushes, air attacks, etc. They were only advancing 15km a day because the Tau were making it impossible to go any faster.
For comparison: The US invasion of Iraq in 2003 only advanced at a rate of 35km a day on average and it was the fastest invasion ever. Luckily, they didn't have to deal with a foe at the level of the Tau.

I'm not confusing anything. That's well over twice as fast against an enemy that's not interested in standing and fighting, simply harassing on the move. We're not talking about stopping and fighting battles; we're talking about raids, snipers, and the occasional fleeting ambush. The Imperial Guard does not really do mobility very well; the Tau raids were why they slowed so much from the planned pace of 20 km/day, which is still much slower than the US invasion of Iraq. A Roman legion might manage that march, although they weren't towing as much artillery.

You'll note its a Vanquisher, which I explicitly said had the best first round kill chances.

And which I explicitly note uses a kinetic subcaliber round with penetration not terribly superior to that of modern tank penetrators.

Land Raider Lascannons are more powerful than their counterparts. Another internally inconsistent bit if you insisted on using the non-canonical rules.

I'm going to challenge that claim and demand you produce evidence. I have counter-evidence already:

Using the Long Fang lascannons they created the first Annihilators, which lead the Space Wolves break out, cutting a swathe through the enemy tanks and Dreadnoughts.

The original tank-killing Annihilators were built using the Wolves' Space-Marine portable lascannon.

For starters, the Chimera has a top speed of 70km\s and the stripped down Trojan has a top speed of 80km\s despite being less than a 10th the weight. Furthermore, the Rhino series can perform at 100% on 50% power and can take additional weight with ease.

Among other things such as high speed scissoring thunder runs by armor in Necropolis, cautious advances at a speed of at least 50kph in Honour Guard and numerous other examples.

Quotes please?

The AdMech treasures century after century reliability (literally), so them governing it more harshly than modern tanks makes sense from their point of view. Its the age old battle between us and the mechs. The mechs never want you to do anything fun.

:p

As for the effect of overcharging, yeah it increases strain and wear on the engine and suspension. So does going fast or doing hard manuevers in a modern tank. Hell, pretty much every moving part on a tank will fail eventually. I've had a drivers hatch fail to open for me on the same day my CVC helmet mic gave out and another tank snapped a track plowing it several feet into the ground during a sagger dril.

The AdMech is just overzealous about preventative measures. Its part of their character along with tech hoarding. Vehicle crews just happen to be luckier than most and can actually work on their own stuff without much AdMech interference.

That, and treads will sometimes fly off at high speeds, depending on how they're constructed. However, they still don't have terribly much horsepower to play around with, and the speed gap is enormous.

That's basically the exact definition of a modern Sabot.

Third-caliber sabots were typical of the 1960s-1970s. Modern discarding-sabot rounds tend to be narrower.

Turning speed\radius is not a direct function of road speed except for the fact that turning radius increases with speed.

Actually, it is. The quickest you can turn - period - is by spinning treads in opposite directions. How fast you can do that is dictated by how fast you can turn the treads and how much power you have - both are limiting factors.

A piece of steel no thicker than my finger, strengthened by radiation casting techniques and impregnated with a sheet of woven diamond fibers, had stopped cold an armor-piercing shell

Remember: Its only modern conventional steel if its 40K.

This is pretty clearly technobabble-reinforced steel. It's compared with conventional steel.

Except for the fact that its all over the place as it mentions standard plasteel construction and you're basically just quoting the same thing over and over again from the same source. I'm still compiling my stuff, but let me leave you with this question: Why is it that you assume its modern RHA without any evidence? What evidence do you have that its modern steel? Why does the steel based battletech armor get a pass from you but you automatically assume the worst for 40K, in defiance of all other evidence? Modern steel can't withstand the kind of impact that would shove a 62 ton vehicle several meters sideways.

BT armor is described as several layers, each of which seems to be nanostructured. That's not conventional steel. Plasteel is not conventional steel either, although its performance is closer.

That quote does differentiate between conventional hardened steel and plasteel, and it is from a source that provides equivalences in conventional steel armor. Nor am I sure that the "conventional steel" is precisely equivalent to modern RHA (although given the authors, it would make sense); but it will be not terribly far away.

Then there's impact angle to consider. If you hit a Land Raider with 300mm "conventional hardened steel" equivalent, say, to 400mm RHA at a 60 degree angle, you're trying to penetrate the equivalent of 800mm RHA.

Hell, an Abrams can't even withstand that much energy by far. A mega IED is enough to utterly mission kill an Abrams, warp the hull beyond repair and transmit enough of the shock into the tank to break bones. The fact that we see none of this on a tank victim to far more energy is telling. The crew all survived with no serious injury and had the tank back at 100% in under an hour.

That's about all I have time for right now.

I would say it is pretty impressive how shock resistant WH40K vehicles are. WH40K weapons do have substantial explosive effects. Resistance to KE penetrators and thickness of armor they can penetrate with their cannon, though, are not numbered among the advantages of WH40K tanks over modern tanks.

[Thanatos]

Ahh, but are not all of those autocannons more powerful than a heavy bolter and less powerful than a battle cannon - per salvo, anyway? That's all I'm asserting here.

No, you have Brostins for example, which was less powerful than a bolter.

Exact quotes, please.

No specific quote for Necropolis, because its based on a body of evidence. A gun position on the walls of Necropolis is 200m and Earthshaker fire from the Zoicans in the plains over the horizon hits the commercia, 10 t0 40km in from the walls. That's 54km to the horizon plus 10-40km not counting how far over the horizon the Zoicans were.

And then:

As the regiment hurridely mustered, sergeants and provosts bellowing at the troopers to gather their weapons and prepare for battle, the drop pods hammered to earth a hundred kilometres or so north-west of the regiment's posiition. Bane knew that another regiment, the 17th Cadian, was encamped in almost the very spot the drop pods were impacting.
...
At last, an artillery spotter attached to the 17th transmitted a desperate request for an artillery barrage to be targeted on his exact position, and Bane immediately routed this to the self-propelled artillery units attached to his regiment. Even as the spotter's transmission degenerated into incoherent screaming, Bane heard the rush of incoming ordnance over the vox-cahnenl and said a silent prayer when it was abruptly cut off as mushroom clouds blossomed on the distant, north-western horizon.

The recoil force backwards on the recoiling assembly is the same as the forward force on the bullet, as is the total change in momentum.

No, the recoil impulse is the same.

Sure it does. It's a hole in the wall that marines rush through.

This is satire right? I said we know nothing about the size of the whole or the properties of the building and you answer with the fact that they can run through it?

I guess a 2m hole in a chicken wire home and blasting a 6m hole in meter thick adobe means exactly the same thing to you?

Length times force gives muzzle energy

No, it doesn't. The Muzzle energy is the kinetic energy of the round being fired and is calculated the exact same way you calculate any other kinetic energy.

And you run an analysis site?

Almost precisely equal to the Earthshaker.

*sigh*
You just completely missed the point. You claimed:

Also note that even the 155m shell you described has a muzzle energy of 6.1 megajoules - not terribly far from a modern kinetic penetrator.

In response to my statement that tank guns were more powerful kinetically than artillery.

A laser weapon similarly capable of piercing the "thickest armor" - but does not ordinarily threaten squads of infantry, unless fired on a special "dispersed" setting.

I guess you're not going to tell anybody that you picked the Fire Prism. Of course it doesn't normally threaten squads of troops on its focused setting, its a focused beam thats only on for less than a second!

A platoon can easily be dispersed across hundreds of meters.

Now, I have presented my case for lascannon being no more than 2 gigajoules in actual effect

No you haven't. You've posted vague reasoning, poorly thought out post facto assumptions and one article you only got because you posted early.

Where did you get your initial 2GJ from?

Actually, it is very real evidence of high firepower (as is instantly setting the entire front of the Aung house on fire), and the sort of incident we don't see in Warhammer, to my knowledge.

What? I gave you one!

And its a plasma weapon, of course it would set the entire front of the house on fire and anyone caught in the blast thanks to the "splash" when it hits. Its not being auto ignited due to heat build up.

Size is enough to be easily visible from a high speed strafing fighter a good distance away.

Yes, its surface area is enough to be seen. If it was say, 5mm thick, than it would need to be 200 square meters, or roughly half an acre, in area to make a full cubic meter of sand.

You don't know the area or the depth. Vague assumptions based on what a pilot can see don't cut it.

The medium laser clearly did most of the work.

No it clearly did not. You can't post something where there's clearly

You just ignored a series of five quotes, which rather precisely established my claims.

I wasn't asking for evidence Short Bus, I was expressing mock surprise you actually posted evidence. Don't tell me you're this lack witted.

Connor McLeod says otherwise in discussing the incident.

Yes he does only you clearly didn't pay any attention to what he says in your link.

IIRC from Honour Guard the terrain was basically "flat" (forest close to a town cleared of trees for about a kilometer's distance.) It was a close range shot (few tens of meters) on ground that inclined slightly downwards from where the Conqueror was (the enemy tank which caused the Conqueror to lurch would be firing upwards.)
The incline probably wasn't significant, though - a laser-cannon armed tank destroyer was able to fire past the Conqueror and destroy the enemy tank very shortly after and the incident is described as bein gnearly parallel IIRC.

How the heck did you interpret that as getting pushed down hill? Was it the part where he explicitly said that it would have been pushed up hill that threw you?

Sideways also means on the axis of least resistance for the treads

No it isn't. The logical failure required to think the above is just staggering. Do you push your car sideways down the road when it breaks down Spock? Do you ride a sled sideways down a hill?

Of course not because its path of most resistance.

vs multi-meganewton legs, hips, etc.

Except for the tiny fact that it would be powered movement since it needs to move to keep its legs under its center of gravity to prevent falling like everything else with legs.

Namely, "Conqueror much better at this."

No you utter dunce. God, it compares it to standard pattern Russ explicitly.

I'm not confusing anything.

Yes you are. You used the rate of advance against the Tau as part of your argument for low speed. Which is stupid because rate of advance is not vehicle speed, as you can tell by one of the fastest invasions on record only maintaining a rate of advance per day equal to half its hourly road speed. Against a foe that it went through like a bullet through Kleenex.

We're not talking about stopping and fighting battles; we're talking about raids, snipers, and the occasional fleeting ambush.

You're conveniently leaving out all that pesky context again.

I guess you forgot about the battle of Tunguska station that not only held up the column but forced it to withdraw and have to retake it late the next day. Odd since you quoted directly from it.

I guess you also missed the repeated mention of frequent stalling attacks that ground the column to a near halt. Odd again, since you quoted from it. Must have just slipped your mind.

I guess you also missed the fact that gaurd units lost 50% of all tank strength in the first few days. Even odder still you again quoted and reffered to events that happened during this.

I also surmise that you forgot that the Tau were continually strafing the Imperial regiments.

I think you also missed the fact that the Imperial supply lines had been cut. and the Imperials were running low on water much less fuel and I guess we can forgive you for missing this, it was only after the line you had quoted.

Another thing you have seem to have missed was the fact that it flat out states that they were managing to move forward despite all this. This one is definitely odd, because it was right before the bit you quoted.

But I guess you just missed or forgot all that and weren't at all being an utter dishonest git by claiming that there wasn't much slowing them down.

A Roman legion might manage that march, although they weren't towing as much artillery.

Oh FFS, a road march is not the same as a god damn combat advance. 20km a day is a good base rate against an enemy on the same level as you.

And which I explicitly note uses a kinetic subcaliber round with penetration not terribly superior to that of modern tank penetrators.

Which you arbitraly assumed to be not terribly superior to modern tank penetrators you mean. Especially since you purposely assumed a round material with less density than Tungsten, reducing the mass of the round by 30%. That's ignoring you don't know the velocity on the Vanquisher gun, even conquerors are described as having hyper velocity rounds.

Then there's impact angle to consider. If you hit a Land Raider with 300mm "conventional hardened steel" equivalent, say, to 400mm RHA at a 60 degree angle, you're trying to penetrate the equivalent of 800mm RHA.

Quite aware of that since I did the calcs for effective armor thickness on the Russ.

I would say it is pretty impressive how shock resistant WH40K vehicles are.

Yet you insist on it being RHA despite that kind of shock resistance not being possible with it.

Actually, it is. The quickest you can turn - period - is by spinning treads in opposite directions

I am aware of pivot steering, you seem to be utterly forgetting what I did for a living. Of course, I know that low end torque and acceleration are what matters, not road speed.

Its all transmission when you're on the move, as a result of being a difference between track speeds. Its NOT road speed that determines turning speed.

And I like how you're still using that ancient HP rating despite basically everything else on there being changed.

[Jedi Master Spock]

Ahh, but are not all of those autocannons more powerful than a heavy bolter and less powerful than a battle cannon - per salvo, anyway? That's all I'm asserting here.

No, you have Brostins for example, which was less powerful than a bolter.

Evidence please. I would like to hear about this autocannon less powerful than a bolter.

Exact quotes, please.

No specific quote for Necropolis, because its based on a body of evidence. A gun position on the walls of Necropolis is 200m and Earthshaker fire from the Zoicans in the plains over the horizon hits the commercia, 10 t0 40km in from the walls. That's 54km to the horizon plus 10-40km not counting how far over the horizon the Zoicans were.

If it's a body of evidence, that means multiple quotes put together. I want to see those quotes.

At that point, assuming that the evidence indeed supports what you claim it does, we have a contradiction. The question is if the 2005 novel overrides the 2003-2007 fluff, along with the direct narrative of the fiction within the 2007 book.

And then:

As the regiment hurridely mustered, sergeants and provosts bellowing at the troopers to gather their weapons and prepare for battle, the drop pods hammered to earth a hundred kilometres or so north-west of the regiment's posiition. Bane knew that another regiment, the 17th Cadian, was encamped in almost the very spot the drop pods were impacting.
...
At last, an artillery spotter attached to the 17th transmitted a desperate request for an artillery barrage to be targeted on his exact position, and Bane immediately routed this to the self-propelled artillery units attached to his regiment. Even as the spotter's transmission degenerated into incoherent screaming, Bane heard the rush of incoming ordnance over the vox-cahnenl and said a silent prayer when it was abruptly cut off as mushroom clouds blossomed on the distant, north-western horizon.

There. I appreciate you at long last providing some evidence. A small question: Where does it say these are Earthshakers? It is the primary artillery of the Guard, of course, so it's not a bad assumption.

A more important question: Which source does this come from, and why should I accept this as overriding the sourcebook fluff of Imperial Armour Volume I, the sourcebook fluff of Imperial Armour Volume III, the sourcebook fluff of Imperial Armour Volume V, and further, the narration, i.e., fiction, of Imperial Armour Volume V, which basically amounts to a novella in and of itself. (The story of the Siege of Vraks.)

The recoil force backwards on the recoiling assembly is the same as the forward force on the bullet, as is the total change in momentum.

No, the recoil impulse is the same.

Clarify. Are you agreeing or disagreeing?

Sure it does. It's a hole in the wall that marines rush through.

This is satire right? I said we know nothing about the size of the whole or the properties of the building and you answer with the fact that they can run through it?

I guess a 2m hole in a chicken wire home and blasting a 6m hole in meter thick adobe means exactly the same thing to you?

Of course not. However, two holes in the wall with similar mission requirements and similar descriptions can be presumed similar.

Length times force gives muzzle energy

No, it doesn't. The Muzzle energy is the kinetic energy of the round being fired and is calculated the exact same way you calculate any other kinetic energy.

Yes, it does. Force (dot) distance is the work done on the round, which is the energy applied to the round, which is the final energy of the shell. Basic physics.

*sigh*
You just completely missed the point. You claimed:

Also note that even the 155m shell you described has a muzzle energy of 6.1 megajoules - not terribly far from a modern kinetic penetrator.

In response to my statement that tank guns were more powerful kinetically than artillery.

That was precisely apt. The ancient 155mm Howitzer is about the KE of a modern kinetic penetrator. And you missed the point earlier that the Earthshaker is a larger gun, and therefore can be expected to have a better ratio of recoil to muzzle energy than the Conqueror, Vanqusher, or Battle Cannon.

For that matter, unless the Vanquisher is under 100mm in caliber, the standard battle cannon less than 50mm, the Conqueror less than 40mm, or the Demolisher less than 30mm, it is the longest weapon in calibers, and gun length in calibers generally correlates strongly and positively with muzzle velocity within a techbase. For that reason, we do not expect muzzle velocities to exceed that of the Earthshaker unless a subcaliber sabot is being used.

Everything we know points to the intuitively obvious solution that the Earthshaker is a high-energy and high-momentum gun by the standards of WH40k armored vehicles.

A laser weapon similarly capable of piercing the "thickest armor" - but does not ordinarily threaten squads of infantry, unless fired on a special "dispersed" setting.

I guess you're not going to tell anybody that you picked the Fire Prism. Of course it doesn't normally threaten squads of troops on its focused setting, its a focused beam thats only on for less than a second!

Precisely. Short firing time, fails to threaten multiple infantrymen at all on that setting. If it were a multi-gigajoule range weapon, it would threaten multiple infantrymen on its high intensity setting, because anything it hit would be exploding violently.

A platoon can easily be dispersed across hundreds of meters.

Squad, not platoon, and "can" is not the same thing as "necessarily." Especially in a universe filled with crew-served field weapons, human/Ork waves, and close-combat formations. The description of the Fire Prism confirms precisely what I've been saying - that a laser weapon powerful enough to pierce the thickest WH40K tank armor does not have a significant area of effect blast.

Now, I have presented my case for lascannon being no more than 2 gigajoules in actual effect

No you haven't. You've posted vague reasoning, poorly thought out post facto assumptions and one article you only got because you posted early.

Where did you get your initial 2GJ from?

I have presented three solid reasons for it. The article in question, while most specific, is hardly the most telling - which is the noticeable lack of blast effects. Note in particular that 2 GJ is the equivalent of a half ton of TNT.

I will now present a fourth line of evidence. To vaporize a 10 cm diameter plug of steel 365mm thick (23 kg): 171 megajoules. Thus, assuming that the thickest value of equivalence given for the protection of Land Raider armor is within a factor of ten of the thermal resistance of actual steel, we conclude (again) that the lascannon is under 2 gigajoules.

In turn, you have presented absolutely no evidence to the counter of my assertion - because, I suspect, you have none that can point to such high lascannon yields.

What? I gave you one!

You most certainly have not presented any example of WH40k ground firepower involving a similar magnitude of collateral damage.

And its a plasma weapon, of course it would set the entire front of the house on fire and anyone caught in the blast thanks to the "splash" when it hits. Its not being auto ignited due to heat build up.

Incorrect on multiple counts. First, the PPC is not a thermal plasma weapon; it is basically a lightning weapon.

The blue lightning missed by less than a meter, striking a nearby rock with a mighty crack!

The brilliant blue bolts of man-made lightning hit a Marauder Atlas in its upper chest just below the skull-like head, sending armor plating ricocheting off in every direction as the bolts seared their way in.

Lightning arced out from the barrels of particle projector cannon, snaking downrange to smash armor into large, molten globs.

As such, it may involve plasma, but it does not splash white-hot plasma everywhere (BT does have such weapons; they are called "plasma cannon" and "plasma rifle"); it involves electrical discharges. Second, the energy requirement I calculated comes not from the house being set on fire, but from the melting glass across the street, something that I have told you several times now.

Incidentally, I made a small mistake the last time I repeated this fact to you. I said I was using a 10m distance for the impact site in the Aungs' yard to the Suthorns' front window, and I gave you a figure that presumed only a 5m distance. The actual figure for 10m is 126 gigajoules.

As I said, it's pretty clear that the PPC is best measured in units of size 10 gigajoules. Personally, I prefer the lower end of this range because of the issue of waste heat, but even the waste heat issue strongly suggests the e10 joule range.

I challenge you to present evidence for PPC yields being less than 10 gigajoules. I have presented two distinct and independent lines of evidence:

• Effect of such weapons and comparable high-intensity short-duration thermal beam weapons against inert normal targets, such as may be seen in Close Quarters.
• Waste heat of such weapons, as illustrated within the rules mechanics as well as in descriptions such as Star Lord.

You have presented nothing - not game mechanical evidence, not descriptive fluff, not narrative fiction, all of which I have examined regarding this topic - and so have no grounds for offering dispute.

Yes, its surface area is enough to be seen. If it was say, 5mm thick, than it would need to be 200 square meters, or roughly half an acre, in area to make a full cubic meter of sand.

5mm is an unlikely thickness. We have a burst of electromagnetic radiation in a tightly focused beam; it's not going to magically conduct itself in a perfect sheet along the surface. Nor, again, do we see WH40k lascannon performing similar feats.

You don't know the area or the depth. Vague assumptions based on what a pilot can see don't cut it.

Is it a precise estimation? No. Is it strongly compatible with what I've outlined? Yes. We generally do not see sand get glassed in anything less than the energy of a strong lightning strike (gigajoules), much less giant splotches of it. We're talking about 1700+ kelvins of heating.

No it clearly did not. You can't post something where there's clearly

Sure it did. It's a far more powerful weapon.

Or would you like to consider how powerful a machine gun would have to be to mow down a grove of trees? With two machine guns and a medium laser, the Locust levelled the grove in seconds. The Locust is a very light-weight, low-firepower BattleMech, among the very lightest and most primitive to be found in the BattleTech militaries - and yet, in the space of moments, it has matched a daisy cutter.

I wasn't asking for evidence

You most certainly seemed to be. I take it, then, that you accept that gauss rifles are 720-1000 megajoule kinetic weapons with 100mm 125 kg rounds?

Yes he does only you clearly didn't pay any attention to what he says in your link.

IIRC from Honour Guard the terrain was basically "flat" (forest close to a town cleared of trees for about a kilometer's distance.) It was a close range shot (few tens of meters) on ground that inclined slightly downwards from where the Conqueror was (the enemy tank which caused the Conqueror to lurch would be firing upwards.)
The incline probably wasn't significant, though - a laser-cannon armed tank destroyer was able to fire past the Conqueror and destroy the enemy tank very shortly after and the incident is described as bein gnearly parallel IIRC.

How the heck did you interpret that as getting pushed down hill? Was it the part where he explicitly said that it would have been pushed up hill that threw you?

The coefficient of static friction generally exceeds the coefficient of kinetic friction. Thus, a jolt that is sufficient to cause an object to start sliding may cause it to lurch downhill, regardless of the direction of the jolt.

There remains, of course, the core issue that what is most likely causing the tank to jolt is not the momentum of the incoming round, but rather the force of its explosion.

No it isn't.

Yes, it is. Treads, if held fixed, present a maximal resistance along the fore/aft axis because the ridges are parallel to the left/right axis. If free to rotate, of course, that doesn't hold. The coefficient of friction also depends on the terrain. It's a very flexible incident that can be modeled in a variety of ways.

Except for the tiny fact that it would be powered movement since it needs to move to keep its legs under its center of gravity to prevent falling like everything else with legs.

The movement being powered makes no difference. The BattleMech offers resistance - likely the full resistance of its leg "muscles" - over whatever distance it shifts. The tank offers resistance - friction - over whatever distance it shifts.

The high center of mass issue is why BattleMechs that get hit particularly hard sometimes fall over. It happens, although as the gauss rifle demonstrates, it usually takes an exceptional quantity of momentum

God, it compares it to standard pattern Russ explicitly.

In saying that, relative to the Conqueror, it has inferior fire-on-the-move capability. Which brings us back to square one.

Yes you are. You used the rate of advance against the Tau as part of your argument for low speed.

The actual rate of advance presented is low; the planned rate of advance was nearly as low.

Which is stupid because rate of advance is not vehicle speed, as you can tell by one of the fastest invasions on record only maintaining a rate of advance per day equal to half its hourly road speed. Against a foe that it went through like a bullet through Kleenex.

What we are presented with is not a running battle. It is a march across a wide open desert which happened to be beset by ambushes and raiders.

You're conveniently leaving out all that pesky context again.

I guess you forgot about the battle of Tunguska station that not only held up the column but forced it to withdraw and have to retake it late the next day. Odd since you quoted directly from it.

One of numerous reasons that the Imperials fell behind their planned schedule for the long march into the desert. Another was the superiority of Tau weapons technology.

The Broadside's railguns, which easily pierce Imperium tank armor, are probably substantially less powerful than the 'Mech scale Gauss Rifle, which has enough momentum to send a Broadside suit flying at >100 m/s. However, they are probably quite close to BT battle armor grade gauss rifles.

I guess you also missed the repeated mention of frequent stalling attacks that ground the column to a near halt. Odd again, since you quoted from it. Must have just slipped your mind.

I guess you also missed the fact that gaurd units lost 50% of all tank strength in the first few days. Even odder still you again quoted and reffered to events that happened during this.

I also surmise that you forgot that the Tau were continually strafing the Imperial regiments.

I think you also missed the fact that the Imperial supply lines had been cut. and the Imperials were running low on water much less fuel and I guess we can forgive you for missing this, it was only after the line you had quoted.

Another thing you have seem to have missed was the fact that it flat out states that they were managing to move forward despite all this. This one is definitely odd, because it was right before the bit you quoted.

All of which the Imperial plans did not account for in their "ambitious" plan to march 20 km per day across the desert and then meet the Tau in a pitched battle.

20 km per day. The long and arduous march across the desert. Hampered by lack of water because of their slow speed and logistical problems; you're mixing up cause and effect there. The march was slow, and therefore, instead of running out of water while they assaulted presumed Tau fortifications, they ran out while trying to get there.

Oh FFS, a road march is not the same as a god damn combat advance. 20km a day is a good base rate against an enemy on the same level as you.

A road march is a lot closer to what the Imperials planned on; a combat advance is what they got, and it was not 20 km a day. Remember, the Imperium commander's planned pace was considered ambitious, and they failed to meet it.

The result was a dramatic display of how badly the Imperials can get themselves beaten by the Tau. They most certainly did not demonstrate exceptional mobility. The Imperium's logistical problems in the Taros campaign, moreover, display limitations on the Guard's common levels of mobility. BattleMech based forces do not require as extensive, slow-moving, and vulnerable a logistics train to support their combat operations.

Which you arbitraly assumed to be not terribly superior to modern tank penetrators you mean.

This is based primarily on their length/diameter ratio, their momentum (less than an Earthshaker round), the apparent caliber of Vanquisher, etc. I have sound reasons for each of my assumptions.

Especially since you purposely assumed a round material with less density than Tungsten, reducing the mass of the round by 30%. That's ignoring you don't know the velocity on the Vanquisher gun, even conquerors are described as having hyper velocity rounds.

You might want to provide a quote to back up any claims about that. Especially given that the depleted uranium is not 30% less dense than tungsten, last I checked.

We do know the muzzle velocity of the Earthshaker, and its mass, and therefore its momentum. We also know that the Earthshaker cannon is substantially more massive (1.5+ times) than the Vanquisher, and thus handles recoil better. If the Vanquisher round has two thirds of the total momentum of an Earthshaker round, meaning if anything more recoil force, and is 13 kg as you have just suggested, then it would have a muzzle velocity of 1586 m/s, and a muzzle energy of 16 megajoules, barely any more than my initial suggestion.

The basic problem here is that no matter what model we use for our ballistics data, the Vanquisher's special anti-tank round is not reasonably going to get within an order of magnitude of the power of a BattleTech gauss rifle. We're talking about something more than twice the muzzle energy of the giant 16"/50 guns of the USS Iowa in a quarter the caliber, and you're thinking that something that measures up to 300mm of conventional steel armor can somehow resist this.

Like the Tau railguns, this will go in one end of the tank and out the other. The hole will be larger, though.

Quite aware of that since I did the calcs for effective armor thickness on the Russ.

By all means, if you have calculations, show them. I remain unimpressed so far, and see no reason to discard the equivalences stated explicitly in the Imperial Armour series.

Yet you insist on it being RHA despite that kind of shock resistance not being possible with it.

Are they made of RHA? No. Of course they do not behave as if constructed of RHA; however, against conventional attacks, they have a resistance equivalent to a certain thickness of conventional steel armor.

Could 300mm of hardened steel armor protect from penetration by a near-proximity gigajaoule blast? It can and it has. Does the shock resistance of a vehicle intrinsically relate to its resistance against penetration? No.

I am aware of pivot steering, you seem to be utterly forgetting what I did for a living. Of course, I know that low end torque and acceleration are what matters, not road speed.
Its all transmission when you're on the move, as a result of being a difference between track speeds. Its NOT road speed that determines turning speed.

And yet, if the maximum speed your treads rotate at is by design 35 kph, then unless you fiddle the engine, the fastest you'll ever turn is going to be with one tread going 35 kph backwards and one going 35 kph forward. This will be the same as running in a circle with the same width as the tank. If it's 3m, for example, the tank is never going to spin 360 degrees in 1 second or less regardless of how much torque or horsepower you have.

This is usually not the limiting factor with real life tanks, but both speed and horsepower can be limiting factors for turning a vehicle, and in the case of the Imperium

And I like how you're still using that ancient HP rating despite basically everything else on there being changed.

Back up your claim, Thanatos. I provided evidence for my claims; it is up to you to provide evidence against them and evidence in favor of your claims. The claim that a source is in error has a double burden: First, to show that it is contradicted by other sources. Second, to show that those other sources are superior.

[Thanatos]

Evidence please. I would like to hear about this autocannon less powerful than a bolter.

It was the one that Brostin carried that I told you about before.

Brostin was suddenly firing. The cannon was kicking out a huge, vibrating sound. One of the enemy monsters was right on them

Not even fazed by Brostin's cannon fire, the Chaos Space Marine thundered forward

Part of the body of evidence for Necropolis.

Out of nowhere, just before nightfall, about a half hour after the klaxons had stopped yelping, the first shells fell, unexpected hurled by long range guns beyond the horizon.
Two fell short on the southern outer habs....

A gigantic salvo hit the railhead at Vayver Gate...

Another scatter pounded the Northern habs along the river...

In mid-stream, Follicks overladen ferry was showered with burning debris... Two more dropped beyond the Magnificat...

A staggered salvo ripped through the mining district...

Volleys of shells and long range missiles pounded into the southern face of the Main Spine.

The guns are over the horizon from the Fort which has the positions at least 200m up

wailing plaintively up at the soldiers two hundred meters above them on the wall top

Which translates to a horizon distance of 55.46km. Thats a minimum distance to the horizon itself. The arty being over the horizon increases that range by quite a bit since you have to take into a account their height. Thats not even taking into account the fact that we don't know how far over the horizon they are.

The distances inside the hive are from the scale map in the book, which since its in Ombnibus form sadly does not fit inside my scanner at all. I'm working on that. It hits as far as the commercia though.

Now, its theorized that the enemy guns are Earthshakers due to them bringing them forward later but we have a reference to the unit on the wall wanting to respond with their Earthshakers but they couldn't without orders from the now insane hive leader.

The question is if the 2005 novel overrides the 2003-2007 fluff, along with the direct narrative of the fiction within the 2007 book.

Why are you listing dates of publication? You're not totally failing to understand the new overwrites old are you?

A more important question: Which source does this come from, and why should I accept this as overriding the sourcebook fluff of Imperial Armour Volume I, the sourcebook fluff of Imperial Armour Volume III, the sourcebook fluff of Imperial Armour Volume V, and further, the narration, i.e., fiction, of Imperial Armour Volume V, which basically amounts to a novella in and of itself. (The story of the Siege of Vraks.)

First off, its from the source you asked for.

Secondly, there is no hierarchy of canon to 40K.

Thirdly, now that I look at it, there is a direct contradiction in IA3 to the other IA books. After a 20km march, they have to pull the Earthshakers forward because they were "were at the extreme edge of their range" and wouldn't be able to support them if they went much further.

Lastly, you're trying to claim different parts of the same book count as different sources?

Clarify. Are you agreeing or disagreeing?

You don't know what impulse is?

However, two holes in the wall with similar mission requirements and similar descriptions can be presumed similar.

No they can't, you don't know what its made of, how thick it is or how wide it is.

Force (dot) distance is the work done on the round, which is the energy applied to the round, which is the final energy of the shell.

*facepalms*

Basic physics.

Its always funny when someone utterly flubs something and tells you how basic it is.

The ancient 155mm Howitzer is about the KE of a modern kinetic penetrator

ABOUT? You call 50% about? Is the Indian Ocean about the size of the Atlantic? Is a 40GB hard drive about the same capacity as a 80GB? Is a half filled glass about full?

6MJ is not about the same muzzle energy as 12MJ unless you have a brain tumor which is becoming a distinct possibility.

And the round in question is not even remotely "ancient"

Precisely. Short firing time, fails to threaten multiple infantrymen at all on that setting.

That's not what it says Spock. It says it can be switched to a dispersed beam to kill squads of infantry.

Squad, not platoon

Squads Spocky, Squads. Notice the plural on it. A platoon is 3 squads plus a small command element.

Especially in a universe filled with crew-served field weapons, human/Ork waves, and close-combat formations.

A squad of infantry in line, echelon or staggered formation (and not using fire teams) in bare minimum combat interval (5m) will have a frontage of roughly 50m.

The description of the Fire Prism confirms precisely what I've been saying -

I like how you keep insisting on using the rules except when it doesn't benefit you:


What's that, a blast effect? You weren't purposely leaving that out were you?

that a laser weapon powerful enough to pierce the thickest WH40K tank armor does not have a significant area of effect blast.

Except that we do have examples of this, such as this one

Flashing across the intervening space, it missed the nose of the still-rising Thunderhawk by what felt like inches. The craft's superstructure groaned and creaked as it was buffeted by the shock-waves of super-heated air. As he jockeyed the flight controls, Salvus muttered a short prayer to the Machine God.

Extreme buffeting from superheated air, enough so to cause stress on a Thunderhawk gunship.

At the center of the killing ground, where the lascannon's discharge slid like an arrow into the earth, the vindictors fell apart at their joints: swallowed in a torus of iridescence that incised bone and sinew like a blade through water. They found themselves blasted up and out on the cusp of a Shockwave; meaty slabs parting along torn seams, shredded alive. This was no great pyrotechnic spectacle, no flaming tumult, no smoke*less fireball: merely a sooty chrysanthemum of uncontainable energy, blindingly bright, that disman*tled its targets like dried leaves before a storm.

Heavy infantry torn apart by the blast effects of a Lascannon hitting the ground near them.

OK, now where's your example of a Lascannon hitting and not presenting what you think is adequate blast effects?

You most certainly have not presented any example of WH40k ground firepower involving a similar magnitude of collateral damage.

Bullshit! I gave you quotes for Jurgens Melta causing flesh to be seared and significant flash burning as a result of super heating the air around it. A triple digit MJ to low GJ event.

I challenge you to present evidence for PPC yields being less than 10 gigajoules.

Easy, direct quote about PPCs hitting:

Striking five tons of heavy munitions with several kilojoules of rampant energy had the effect one might think.

I'll have more as soon as the rest of the stuff downloads....err, gets here in the mail.
But I already have a direct

5mm is an unlikely thickness.

It was a sample thickness to point out how you need to know the depth before you can judge it.

Or would you like to consider how powerful a machine gun would have to be to mow down a grove of trees?

I don't think you understand how powerful a machine gun you need to cut down trees

You can cut down a single tree with 400 rounds firedfrom a Vickers with a number of rounds going wode (.303) and far less accurate firing from a M134 (7.62mm Nato) cancut down a mesquite tree in 1:08 with almost all of the rounds clearly going wide. Rounds that would quite often hit nearby trees.

But this is just small arms fire. We're not even into the fifty cal range and we have a weapon that could cut down a tree easily. From a quick glance, Battletech MGs tend to be in the 20mm range, which would be ludicrous to assume that they couldn't easily cut down trees.

Of course, lets not forget the small laser which will probably be downing a tree in direct fire probably every shot.

Not however, by any "daisy cutter" effect. That's just your delusion.

The coefficient of static friction generally exceeds the coefficient of kinetic friction. Thus, a jolt that is sufficient to cause an object to start sliding may cause it to lurch downhill, regardless of the direction of the jolt.

Quit your bullshitting Spock. You claimed it was pushed downhill and was therefore not that impressive. I asked where you got that impression. You tried to back that up by claiming that Conner said it got pushed downhill when he didn't.

The tank did not get pushed downhill, so quit the bullshit.

In saying that, relative to the Conqueror, it has inferior fire-on-the-move capability.

How can you keep being this stupid? Lets pay attention to the quote shall we?

The AT83 Brigands, larger than their more primitive cousins the 70s, were, on paper, the Urdeshi forge world's equivalent of the Leman Russ. They had auspex guidance, weapon stabilisers and torsion bar suspension. They were the Blood Pact's best battle machines, not counting the very few ancient super-heavies they had inherited from defeated Guard units."

It's a very flexible incident that can be modeled in a variety of ways.

Read As: I'm going to try to bullshit like crazy in an attempt to low ball it. But this isn't even remotely the end of your falsehoods.

It is a march across a wide open desert which happened to be beset by ambushes and raiders.

Man you are just plain dumb. The Imperials planned on a 20km a day advance. Slowed down by constant attacks, they slowed down to an average rate of 15km. This means that on foot and under constant attack, they managed to maintain a daily rate of advance only half of that of the entirely mechanized Invasion of Iraq.

20km a day is a reasonable rate of advance (especially with typical British "pull forward a bit and consolidate"), you just don't know a Mauser rifle from a Javelin.

All of which the Imperial plans did not account for in their "ambitious" plan to march 20 km per day across the desert and then meet the Tau in a pitched battle.

Bullshit again.

De Stael's offensive timetable called for the Tallarn regiments to make an ambitious twenty kms a day, but he expected that in some sectors along the front the Tau would stand and fight and that sector would naturally be slowed down or halted by combat. If the Tau committed their forces to battle in one sector, then others sectors would be able to move faster. De Stael's staff believes an average of twenty kms a day should be sustainable, especially as the Tallarn units would be operating in a familiar environment.

De Stael expected combat along the way. It was part of his insanely stupid plan that there would be heavy fighting in certain sectors and that everyone else would slip by.

There's also the Guardsmen in the advance being utterly surprised when they didn't meet any resistance the first day, the fact that they started off the advance with a full creeping barrage and hit likely places the next day.

The Imperium's logistical problems in the Taros campaign, moreover, display limitations on the Guard's common levels of mobility.

Not really, since Taros was atypical. First of all, the 13th Black Crusade was on. That massively sapped logistics as they were sending almost everything they could spare at it. They could barely get men to send there, much less supply them well.

Not to mention political matters and utter, utter stupidity on the part of Gustavus and De Stael.

Plus they always have to gimp the Guard due to the canonical fact that the Tau don't stand a chance in a full scale war against the Imperium. ;)

You might want to provide a quote to back up any claims about that.

With pleasure:

Heedless of the 105mm shells tearing into the highway and trees around him, Sirus confronted the Infardi armour head-on. The Wrath of Pardua sped forward with a clank of treads and fired its main gun. The hypervelocity round hit the nearest of the two enemy vehicles, exploding into the rear mantlet of its turret with such forcec the entire turret mount spun round through two hundreds and ten degrees. The tank clearly retained motive power, because it continued to churn along the road, but its traverse system was crippled and the turret and weapon swung around slackly with the motion.

An AT70 lobbed a shell at the Wild One that tore away its sponson and part of its track skirt. Another hit the Demands With Menaces on the turret destroying its vox-mast, pintle mount and laser range-finder, and killing the assistant gunner with explosive spalling.
Wounded but not down, the Demands With Menaces plunged forward, laying its guns at the Reaver responsible. Corbec saw the top-hatch pop and the commander emerge, oblivious to the danger, to verify aim with a handscope now his range-finder was junked.
He knew his job. The Demands rolled to a halt and jolted hard as it fired, jerking plumes of accumulated white dust off its surfaces and hull grooves like sifted flour. The sound of the hypervelocity AT shell was just a crisp, flat clap in the augmented air. The AT70 made a much fuller and more satisfying sound as it exploded.

Especially given that the depleted uranium is not 30% less dense than tungsten, last I checked.

Well then you fucked up your math.

By all means, if you have calculations, show them. I remain unimpressed so far, and see no reason to discard the equivalences stated explicitly in the Imperial Armour series.

*sigh*
Effective thickness is the relative thickness based on the angle of the slope of the armor. I used the Imperial Armor figures for them when I calculated the thickness, so they're not going to contradict them are they?

And yet, if the maximum speed your treads rotate at is by design 35 kph, then unless you fiddle the engine, the fastest you'll ever turn is going to be with one tread going 35 kph backwards and one going 35 kph forward.

*beats head against desk*
Its. Not. The. Road. Speed.

If it's 3m, for example, the tank is never going to spin 360 degrees in 1 second or less regardless of how much torque or horsepower you have.

Sweet Jesus, you think that's a bad thing it can't do a full rotation in under a second? :eek:

Back up your claim, Thanatos.

Easy.




The vehicle weight, listed speeds, crew duties, loading mechanism, completely different internal arrangement, etc.

[Thanatos]

Evidence please. I would like to hear about this autocannon less powerful than a bolter.

It was the one that Brostin carried that I told you about before.

Brostin was suddenly firing. The cannon was kicking out a huge, vibrating sound. One of the enemy monsters was right on them

Not even fazed by Brostin's cannon fire, the Chaos Space Marine thundered forward

Part of the body of evidence for Necropolis.

Out of nowhere, just before nightfall, about a half hour after the klaxons had stopped yelping, the first shells fell, unexpected hurled by long range guns beyond the horizon.
Two fell short on the southern outer habs....

A gigantic salvo hit the railhead at Vayver Gate...

Another scatter pounded the Northern habs along the river...

In mid-stream, Follicks overladen ferry was showered with burning debris... Two more dropped beyond the Magnificat...

A staggered salvo ripped through the mining district...

Volleys of shells and long range missiles pounded into the southern face of the Main Spine.

The guns are over the horizon from the Fort which has the positions at least 200m up

wailing plaintively up at the soldiers two hundred meters above them on the wall top

Which translates to a horizon distance of 55.46km. Thats a minimum distance to the horizon itself. The arty being over the horizon increases that range by quite a bit since you have to take into a account their height. Thats not even taking into account the fact that we don't know how far over the horizon they are.

The distances inside the hive are from the scale map in the book, which since its in Ombnibus form sadly does not fit inside my scanner at all. I'm working on that. It hits as far as the commercia though.

Now, its theorized that the enemy guns are Earthshakers due to them bringing them forward later but we have a reference to the unit on the wall wanting to respond with their Earthshakers but they couldn't without orders from the now insane hive leader.

The question is if the 2005 novel overrides the 2003-2007 fluff, along with the direct narrative of the fiction within the 2007 book.

Why are you listing dates of publication? You're not totally failing to understand the new overwrites old are you?

A more important question: Which source does this come from, and why should I accept this as overriding the sourcebook fluff of Imperial Armour Volume I, the sourcebook fluff of Imperial Armour Volume III, the sourcebook fluff of Imperial Armour Volume V, and further, the narration, i.e., fiction, of Imperial Armour Volume V, which basically amounts to a novella in and of itself. (The story of the Siege of Vraks.)

First off, its from the source you asked for.

Secondly, there is no hierarchy of canon to 40K.

Thirdly, now that I look at it, there is a direct contradiction in IA3 to the other IA books. After a 20km march, they have to pull the Earthshakers forward because they were "were at the extreme edge of their range" and wouldn't be able to support them if they went much further.

Lastly, you're trying to claim different parts of the same book count as different sources?

Clarify. Are you agreeing or disagreeing?

You don't know what impulse is?

However, two holes in the wall with similar mission requirements and similar descriptions can be presumed similar.

No they can't, you don't know what its made of, how thick it is or how wide it is.

Force (dot) distance is the work done on the round, which is the energy applied to the round, which is the final energy of the shell.

*facepalms*

Basic physics.

Its always funny when someone utterly flubs something and tells you how basic it is.

The ancient 155mm Howitzer is about the KE of a modern kinetic penetrator

ABOUT? You call 50% about? Is the Indian Ocean about the size of the Atlantic? Is a 40GB hard drive about the same capacity as a 80GB? Is a half filled glass about full?

6MJ is not about the same muzzle energy as 12MJ unless you have a brain tumor which is becoming a distinct possibility.

And the round in question is not even remotely "ancient"

Precisely. Short firing time, fails to threaten multiple infantrymen at all on that setting.

That's not what it says Spock. It says it can be switched to a dispersed beam to kill squads of infantry.

Squad, not platoon

Squads Spocky, Squads. Notice the plural on it. A platoon is 3 squads plus a small command element.

Especially in a universe filled with crew-served field weapons, human/Ork waves, and close-combat formations.

A squad of infantry in line, echelon or staggered formation (and not using fire teams) in bare minimum combat interval (5m) will have a frontage of roughly 50m.

The description of the Fire Prism confirms precisely what I've been saying -

I like how you keep insisting on using the rules except when it doesn't benefit you:


What's that, a blast effect? You weren't purposely leaving that out were you?

that a laser weapon powerful enough to pierce the thickest WH40K tank armor does not have a significant area of effect blast.

Except that we do have examples of this, such as this one

Flashing across the intervening space, it missed the nose of the still-rising Thunderhawk by what felt like inches. The craft's superstructure groaned and creaked as it was buffeted by the shock-waves of super-heated air. As he jockeyed the flight controls, Salvus muttered a short prayer to the Machine God.

Extreme buffeting from superheated air, enough so to cause stress on a Thunderhawk gunship.

At the center of the killing ground, where the lascannon's discharge slid like an arrow into the earth, the vindictors fell apart at their joints: swallowed in a torus of iridescence that incised bone and sinew like a blade through water. They found themselves blasted up and out on the cusp of a Shockwave; meaty slabs parting along torn seams, shredded alive. This was no great pyrotechnic spectacle, no flaming tumult, no smoke*less fireball: merely a sooty chrysanthemum of uncontainable energy, blindingly bright, that disman*tled its targets like dried leaves before a storm.

Heavy infantry torn apart by the blast effects of a Lascannon hitting the ground near them.

OK, now where's your example of a Lascannon hitting and not presenting what you think is adequate blast effects?

You most certainly have not presented any example of WH40k ground firepower involving a similar magnitude of collateral damage.

Bullshit! I gave you quotes for Jurgens Melta causing flesh to be seared and significant flash burning as a result of super heating the air around it. A triple digit MJ to low GJ event.

I challenge you to present evidence for PPC yields being less than 10 gigajoules.

Easy, direct quote about PPCs hitting:

Striking five tons of heavy munitions with several kilojoules of rampant energy had the effect one might think.

I'll have more as soon as the rest of the stuff downloads....err, gets here in the mail.
But I already have a direct

5mm is an unlikely thickness.

It was a sample thickness to point out how you need to know the depth before you can judge it.

Or would you like to consider how powerful a machine gun would have to be to mow down a grove of trees?

I don't think you understand how powerful a machine gun you need to cut down trees

You can cut down a single tree with 400 rounds firedfrom a Vickers with a number of rounds going wode (.303) and far less accurate firing from a M134 (7.62mm Nato) cancut down a mesquite tree in 1:08 with almost all of the rounds clearly going wide. Rounds that would quite often hit nearby trees.

But this is just small arms fire. We're not even into the fifty cal range and we have a weapon that could cut down a tree easily. From a quick glance, Battletech MGs tend to be in the 20mm range, which would be ludicrous to assume that they couldn't easily cut down trees.

Of course, lets not forget the small laser which will probably be downing a tree in direct fire probably every shot.

Not however, by any "daisy cutter" effect. That's just your delusion.

The coefficient of static friction generally exceeds the coefficient of kinetic friction. Thus, a jolt that is sufficient to cause an object to start sliding may cause it to lurch downhill, regardless of the direction of the jolt.

Quit your bullshitting Spock. You claimed it was pushed downhill and was therefore not that impressive. I asked where you got that impression. You tried to back that up by claiming that Conner said it got pushed downhill when he didn't.

The tank did not get pushed downhill, so quit the bullshit.

In saying that, relative to the Conqueror, it has inferior fire-on-the-move capability.

How can you keep being this stupid? Lets pay attention to the quote shall we?

The AT83 Brigands, larger than their more primitive cousins the 70s, were, on paper, the Urdeshi forge world's equivalent of the Leman Russ. They had auspex guidance, weapon stabilisers and torsion bar suspension. They were the Blood Pact's best battle machines, not counting the very few ancient super-heavies they had inherited from defeated Guard units."

It's a very flexible incident that can be modeled in a variety of ways.

Read As: I'm going to try to bullshit like crazy in an attempt to low ball it. But this isn't even remotely the end of your falsehoods.

It is a march across a wide open desert which happened to be beset by ambushes and raiders.

Man you are just plain dumb. The Imperials planned on a 20km a day advance. Slowed down by constant attacks, they slowed down to an average rate of 15km. This means that on foot and under constant attack, they managed to maintain a daily rate of advance only half of that of the entirely mechanized Invasion of Iraq.

20km a day is a reasonable rate of advance (especially with typical British "pull forward a bit and consolidate"), you just don't know a Mauser rifle from a Javelin.

All of which the Imperial plans did not account for in their "ambitious" plan to march 20 km per day across the desert and then meet the Tau in a pitched battle.

Bullshit again.

De Stael's offensive timetable called for the Tallarn regiments to make an ambitious twenty kms a day, but he expected that in some sectors along the front the Tau would stand and fight and that sector would naturally be slowed down or halted by combat. If the Tau committed their forces to battle in one sector, then others sectors would be able to move faster. De Stael's staff believes an average of twenty kms a day should be sustainable, especially as the Tallarn units would be operating in a familiar environment.

De Stael expected combat along the way. It was part of his insanely stupid plan that there would be heavy fighting in certain sectors and that everyone else would slip by.

There's also the Guardsmen in the advance being utterly surprised when they didn't meet any resistance the first day, the fact that they started off the advance with a full creeping barrage and hit likely places the next day.

The Imperium's logistical problems in the Taros campaign, moreover, display limitations on the Guard's common levels of mobility.

Not really, since Taros was atypical. First of all, the 13th Black Crusade was on. That massively sapped logistics as they were sending almost everything they could spare at it. They could barely get men to send there, much less supply them well.

Not to mention political matters and utter, utter stupidity on the part of Gustavus and De Stael.

Plus they always have to gimp the Guard due to the canonical fact that the Tau don't stand a chance in a full scale war against the Imperium. ;)

You might want to provide a quote to back up any claims about that.

With pleasure:

Heedless of the 105mm shells tearing into the highway and trees around him, Sirus confronted the Infardi armour head-on. The Wrath of Pardua sped forward with a clank of treads and fired its main gun. The hypervelocity round hit the nearest of the two enemy vehicles, exploding into the rear mantlet of its turret with such forcec the entire turret mount spun round through two hundreds and ten degrees. The tank clearly retained motive power, because it continued to churn along the road, but its traverse system was crippled and the turret and weapon swung around slackly with the motion.

An AT70 lobbed a shell at the Wild One that tore away its sponson and part of its track skirt. Another hit the Demands With Menaces on the turret destroying its vox-mast, pintle mount and laser range-finder, and killing the assistant gunner with explosive spalling.
Wounded but not down, the Demands With Menaces plunged forward, laying its guns at the Reaver responsible. Corbec saw the top-hatch pop and the commander emerge, oblivious to the danger, to verify aim with a handscope now his range-finder was junked.
He knew his job. The Demands rolled to a halt and jolted hard as it fired, jerking plumes of accumulated white dust off its surfaces and hull grooves like sifted flour. The sound of the hypervelocity AT shell was just a crisp, flat clap in the augmented air. The AT70 made a much fuller and more satisfying sound as it exploded.

Especially given that the depleted uranium is not 30% less dense than tungsten, last I checked.

Well then you fucked up your math.

By all means, if you have calculations, show them. I remain unimpressed so far, and see no reason to discard the equivalences stated explicitly in the Imperial Armour series.

*sigh*
Effective thickness is the relative thickness based on the angle of the slope of the armor. I used the Imperial Armor figures for them when I calculated the thickness, so they're not going to contradict them are they?

And yet, if the maximum speed your treads rotate at is by design 35 kph, then unless you fiddle the engine, the fastest you'll ever turn is going to be with one tread going 35 kph backwards and one going 35 kph forward.

*beats head against desk*
Its. Not. The. Road. Speed.

If it's 3m, for example, the tank is never going to spin 360 degrees in 1 second or less regardless of how much torque or horsepower you have.

Sweet Jesus, you think that's a bad thing it can't do a full rotation in under a second? :eek:

Back up your claim, Thanatos.

Easy.




The vehicle weight, listed speeds, crew duties, loading mechanism, completely different internal arrangement, etc.

[Jedi Master Spock]

It was the one that Brostin carried that I told you about before.

Brostin was suddenly firing. The cannon was kicking out a huge, vibrating sound. One of the enemy monsters was right on them

Not even fazed by Brostin's cannon fire, the Chaos Space Marine thundered forward

And that doesn't tell us about its relative total muzzle energy output vs a bolter. A CSM can potentially survive bolter fire as well, can it not?

Part of the body of evidence for Necropolis.

Out of nowhere, just before nightfall, about a half hour after the klaxons had stopped yelping, the first shells fell, unexpected hurled by long range guns beyond the horizon.
Two fell short on the southern outer habs....

A gigantic salvo hit the railhead at Vayver Gate...

Another scatter pounded the Northern habs along the river...

In mid-stream, Follicks overladen ferry was showered with burning debris... Two more dropped beyond the Magnificat...

A staggered salvo ripped through the mining district...

Volleys of shells and long range missiles pounded into the southern face of the Main Spine.

The guns are over the horizon from the Fort which has the positions at least 200m up

wailing plaintively up at the soldiers two hundred meters above them on the wall top

Which translates to a horizon distance of 55.46km. Thats a minimum distance to the horizon itself. The arty being over the horizon increases that range by quite a bit since you have to take into a account their height. Thats not even taking into account the fact that we don't know how far over the horizon they are.

Provided, of course, that we're dealing with level terrain.

The distances inside the hive are from the scale map in the book, which since its in Ombnibus form sadly does not fit inside my scanner at all. I'm working on that. It hits as far as the commercia though.

Now, its theorized that the enemy guns are Earthshakers due to them bringing them forward later but we have a reference to the unit on the wall wanting to respond with their Earthshakers but they couldn't without orders from the now insane hive leader.

The question is if the 2005 novel overrides the 2003-2007 fluff, along with the direct narrative of the fiction within the 2007 book.

Why are you listing dates of publication? You're not totally failing to understand the new overwrites old are you?

Precisely. The Siege of Vraks, which reiterates and reinforces the 15-16 km effective range under roughly T-normal conditions, came out in late 2007, while the incident you reference comes from 2005.

First off, its from the source you asked for.

Secondly, there is no hierarchy of canon to 40K.

Thirdly, now that I look at it, there is a direct contradiction in IA3 to the other IA books. After a 20km march, they have to pull the Earthshakers forward because they were "were at the extreme edge of their range" and wouldn't be able to support them if they went much further.

Lastly, you're trying to claim different parts of the same book count as different sources?

Potentially different types of canon; however, that it exists in both types of canon means that it's a stronger example for it.

Note, further, that it's the normal range, and that they have available for the towed Earthshakers the "extreme" range option of using charges 6-7. Thus, 20 km being the "extreme edge of their range" is not particularly striking - especially considering how sensitive artillery is to local variation in gravity and atmospheric density. Taros has a local g value of Tx.96, Vraks has a local g value of Tx1.05. Objects fall ~9% faster on Vraks. Variation in atmospheric resistance is even more important. So, a weapon rated for 16 km in T-normal conditions might fly 15 km on one planet and 20 km on another.

It's pretty reasonable to assume that most of the descriptions approximate T-normal conditions, and that some variance is due to local planetary conditions, while some is due to variance in manufacture from Forge World to Forge World.

You don't know what impulse is?

I do. So make up your mind whether you're trying to agree or disagree with me on this point. Your statement was ambiguous on that count.

No they can't, you don't know what its made of, how thick it is or how wide it is.

And?

Force (dot) distance is the work done on the round, which is the energy applied to the round, which is the final energy of the shell.

*facepalms*

Basic physics.

Its always funny when someone utterly flubs something and tells you how basic it is.

Thanatos, I've not flubbed a thing. If you don't care to take my word for the fact that force dot distance gives the work done on an object, you might try Hyperphysics,, Wikipedia, Yahoo Answers, various other instructional websites, or you could go ask on the physics forums.

What I'm describing is a basic law of kinematics, taught in just about every introductory physics course.

ABOUT?[/i] You call 50% about? Is the Indian Ocean about the size of the Atlantic? Is a 40GB hard drive about the same capacity as a 80GB? Is a half filled glass about full?

6MJ is not about the same muzzle energy as 12MJ unless you have a brain tumor which is becoming a distinct possibility.

As noted in my explanation to l33telboi about discarding sabot rounds, the energy of the M829A1 kinetic penetrator - not the total round including sabot - is about 6.2 MJ shortly after firing. I expected that you were already aware of that distinction.

Now, the M829A3 is a much nicer round, and probably has 7-8 MJ energy on the penetrator initially, but the M829A1 is the one I had figures for. As I said, that [reasonably modern] kinetic penetrator, which is probably still better than what many less professional militaries have lying around, has similar energy at point blank as the 155mm Howitzer - 6.2 MJ vs 6.1 MJ.

And the round in question is not even remotely "ancient"

Depends on your value for ancient. You were describing it as old, yourself - we were talking about WWII era artillery when you brought it up.

Precisely. Short firing time, fails to threaten multiple infantrymen at all on that setting.

That's not what it says Spock. It says it can be switched to a dispersed beam to kill squads of infantry.

Squad, not platoon

Squads Spocky, Squads. Notice the plural on it. A platoon is 3 squads plus a small command element.

Especially in a universe filled with crew-served field weapons, human/Ork waves, and close-combat formations.

A squad of infantry in line, echelon or staggered formation (and not using fire teams) in bare minimum combat interval (5m) will have a frontage of roughly 50m.

The description of the Fire Prism confirms precisely what I've been saying -

I like how you keep insisting on using the rules except when it doesn't benefit you:
What's that, a blast effect? You weren't purposely leaving that out were you?

No, I'd stopped bothering to look at the game mechanical descriptions at that point, as you seemed impervious to game-mechanical arguments.

that a laser weapon powerful enough to pierce the thickest WH40K tank armor does not have a significant area of effect blast.

Except that we do have examples of this, such as this one

Flashing across the intervening space, it missed the nose of the still-rising Thunderhawk by what felt like inches. The craft's superstructure groaned and creaked as it was buffeted by the shock-waves of super-heated air. As he jockeyed the flight controls, Salvus muttered a short prayer to the Machine God.

Extreme buffeting from superheated air, enough so to cause stress on a Thunderhawk gunship.

At the center of the killing ground, where the lascannon's discharge slid like an arrow into the earth, the vindictors fell apart at their joints: swallowed in a torus of iridescence that incised bone and sinew like a blade through water. They found themselves blasted up and out on the cusp of a Shockwave; meaty slabs parting along torn seams, shredded alive. This was no great pyrotechnic spectacle, no flaming tumult, no smoke*less fireball: merely a sooty chrysanthemum of uncontainable energy, blindingly bright, that disman*tled its targets like dried leaves before a storm.

Heavy infantry torn apart by the blast effects of a Lascannon hitting the ground near them.

OK, now where's your example of a Lascannon hitting and not presenting what you think is adequate blast effects?

At long last you provide evidence for lascannon causing collateral damage. So, we must conclude that they can indeed do so. However, neither does either case require exceptional (>2 GJ) yields, and there remain the other three lines of evidence against you.

In fact, the infantry case, closest to quantifiable, we see no evidence of ignition of the infantry or partial or full vaporization. If we assumed that the blast was 1 km/s debris with enough momentum to launch 100 kg/m^2 at 10 m/s at 5m, and that half the energy was released in blast form and half in radiant heat, both omnidirectionally (i.e., including into the ground), that would be 314 megajoules.

So you're still nowhere near showing >2 GJ yields. The best example for that which I am aware of is the Tau battlesuit melting case we discussed earlier, and as I pointed out, that's actually a fairly flexible example. In addition to that example, with very limited heating effects and sub-GJ range blast effects (we don't even have a large crater mentioned in that quote), we have the Inferno spread, giving rare explicit figures, we have the hellgun powerpacks and hellgun/lasgun effective yields vs nominal consumption levels, and we have the equivalent thicknesses of steel that WH40k vehicles are protected by. We also have its lack of in-game blast effects, which are present on definitively stronger weapons (such as the laser destroyer and turbo-laser destructor) as well as high explosive weapons substantially less powerful than the Earthshaker.

I'll now [re]introduce three more suggestive items to make the list complete. Sixth: The lascannon is the secondary weapon of the Leman Russ. The primary weapon, the Battle Cannon, is less powerful than the Earthshaker, which per the previously quoted passage in Honour Guard, has a ~2 GJ HE bursting charge and therefore generally nails a target with about a gigajoule on flat-surface impact.

Seventh: The melta, per Caves of Ice and the lack of explosive overpressure, can come up with ~30 GJ at a rate of 1-10 GW or so. Per the little door-melting (not vaporizing) incident of Vraks, and the flesh-bursting example you provided, we really don't expect more than a couple gigajoules for a melta burst in combat. And the melta, though a credible anti-tank weapon at point-blank ranges, is much less focused than the lascannon, in terms of time of impact and impact area.

Eighth: You've had about a month to come up with some kind of quantifiable lascannon event pointing to >2 GJ yields, and haven't come up with a single one. If there's any evidence pointing to that, it's buried deep among all the evidence that suggests a lascannon is somewhere at or below 2 GJ that we've both rifled through. It's not as if this is a particularly unusual conclusion; this is the same sort of order of magnitude that debaters seem pretty willing to accept.

For example, Connor MacLeod on SDN, pretty clearly interested in promoting higher WH40k numbers, gives "high triple digit MJ to low single digit GJ," "in the hundreds of MJ easily," "las cannon have a minimum energy output of hundreds of megajoules", and once - for the example we discussed at greater length earlier, the Tau battlesuit case - concluding 2-4 GJ by treating the battlesuit as an inert solid brick of steel. If there was anything resembling solid evidence for lascannon yield >2 GJ, I feel like it should have seen the light of day by now.

I rest upon eightfold path of lascannon yield certainty. The lascannon has an effective yield of no more than two times ten to the ninth kilogram meters squared per second squared.

Bullshit! I gave you quotes for Jurgens Melta causing flesh to be seared and significant flash burning as a result of super heating the air around it. A triple digit MJ to low GJ event.

Triple digit MJ to maybe low GJ is not the same order of magnitude as an event that at a minimum is in the tens of gigajoules. To be precise, it's two orders of magnitude lower. So no, you haven't shown anything with the sort of magnitude of collateral damage I've shown.

Easy, direct quote about PPCs hitting:

Striking five tons of heavy munitions with several kilojoules of rampant energy had the effect one might think.

I'll have more as soon as the rest of the stuff downloads....err, gets here in the mail.
But I already have a direct

"Several kilojoules," for the total energy of the PPC bolt, unfortunately, is contradicted implicitly by every other description, including the ones that I didn't previously cite in this thread:

The metal monster rocked, turned. The blue lightning from its left arm hit the next street over, sending a rush of debris riding skyward on an orange fireball.

Glass and structural steel puffed away from laser and PPC caresses in vapor; brick and granite blew apart in blossoms of dust.

Even as she turned, the yellow hellglare of the Griff's PPC lit up the buildings to either side. The big Mauler rocked from the recoil effect of New Samarkand's finest ferro-fibrous armor jetting away from the beam in the form of plasma.

The blue lightning missed by less than a meter, striking a nearby rock with a mighty crack!

The 'Mech tottered back slightly under the hit, losing some of its speed and momentum as the PPC blasted a huge hole in its chest. A wave of heat washed over her as the temperature in the cockpit suddenly spiked...

The bright beams of the enemy 'Mech's twin PPCs boiled away his torso armor in a thunder-like clap of arcing electrical energy, leaving billowing black smoke where the armor had torn away. The impact was vicious, and Trent's balance swayed slightly, throwing off his targeting sight.

The sudden impact forced Jez's shots low, her PPC stabbing up into the black mire of the swamp, sending dancing arcs of blue energy over the water and billows of steam into the evening sky.

Her PPC carved into the Nightsky's back, slicing through engine shielding and splashing molten titanium down into the spinning gyro.

The arcs of twin PPCs scoured his legs, crisping more of his protection into impotent slag.

The Nightstar's PPC scarred the Templar's left side with molten cuts,

Luckily the Caesar's ER PPC missed low and to the right, turning a parked hovercar into a small sunburst shattering any remaining unbroken glass in a nearby bakery.

The Grand Dragon and the Grasshopper charged forward, taking out dozens of soldiers with every PPC and laser salvo.

Chu's Orion took a PPC bolt square in the chest, the lightning bolt discharge from the hull fusing sand to glass by his 'Mech's feet, the blast leaving a gaping, smoke-belching crater just below the Orion's cockpit.

And even this:

There was a good chance the weapon would be destroyed in such an attack, fused into a massive slug of ferro-titanium, but it did allow him to fire at incredibly deadly ranges.

As, after all, the PPC is very likely to have more than 0.0001% efficiency...

For reference, several kilojoules will melt several grams of whatever. We're talking about small arms fire on this scale of energy. Every one of these contradicts that notion of yours; then we also have every example involving lasers that aren't supposed to outmatch the PPC, etc. "Several kilojoules" here is if anything less viable than using it for Star Wars fighters based on similar quotes, and I've always described that as a serious stretch.

The low megajoule figures cited in BattleTechnology #3 would fail similarly, except for the fact that BattleTechnology #4, in one stroke, retcons them by a factor of 1,000, and in the same issue demonstrates conclusively that the people at BattleTechnology could not put watts, joules, and seconds together correctly to save their own lives, rendering the entire set of BattleTechnology energy/power figures suspect.

Which is a pity, because I thought their laser rifle and laser pistol figures didn't look too bad. We still have a handful of arbitrary sounding quotes, like this one:

The destructive energy washed down the side of the Falconer's long torso, burning away armor and splashing it to the ground in impotent pools. Several megajoules of energy cored through to shave away physical shielding from around the Falconer's fusion reactor, forcing it to shut down or risk a catastrophic containment failure.

Except that the "megajoules" are a small part of the weapon's yield, that penetrating the armor and going through. From the huge numbers of descriptions of large-scale melting, vaporization, and collateral damage, any claim of less than hundreds of megajoules is outright absurd; any claim of less than gigajoules needs to deal with the waste heat issues and the specifics of some of those collateral damage incidents.

5mm is an unlikely thickness.

It was a sample thickness to point out how you need to know the depth before you can judge it.

Except that we can make much better guesses about the probable thickness and size. We've seen what kind of effects cause fring melting of sand, e.g., powerful lightning bolts - and a laser is a much more focused spurt of energy. We have every reason to guess that this is somewhere over a gigajoule just from the description; how much more, we cannot tell, but any guess that looks like less than 100 MJ or more than 100 GJ is outright absurd.

Or would you like to consider how powerful a machine gun would have to be to mow down a grove of trees?

I don't think you understand how powerful a machine gun you need to cut down trees

You can cut down a single tree with 400 rounds firedfrom a Vickers with a number of rounds going wode (.303) and far less accurate firing from a M134 (7.62mm Nato) cancut down a mesquite tree in 1:08 with almost all of the rounds clearly going wide. Rounds that would quite often hit nearby trees.

But this is just small arms fire. We're not even into the fifty cal range and we have a weapon that could cut down a tree easily. From a quick glance, Battletech MGs tend to be in the 20mm range, which would be ludicrous to assume that they couldn't easily cut down trees.

Of course, lets not forget the small laser which will probably be downing a tree in direct fire probably every shot.

It's not a small laser; it's a medium laser, the same class of weapon seen causing tree trunks to explode in steam (as an unintented fringe effect) in the same battle:

A Quickdraw rises next, muck cascading from the sagittal crest fore-and-afting its round head, arms raised to pump dazzling laser pulses at phantom foes in the woods. Tree trunks explode in steam as the 'Mech rises high on its jump jets.

Now, that's firing 5.3 kg of bullets (470 x 11.3g; more like 10 kg of ammunition belt) hitting that one tree perfectly to knock it down in one minute of firing. We're not talking about chopping down a tree in one minute with a carefully aimed burst; we're talking about levelling an entire grove in frenzied seconds while Cassie, IIRC, runs to a carefully prepared mudpit nearby to lure it in.

I will grant that BT MGs are rather more powerful than the weapons you're talking about; however, they're still much less powerful than the medium laser by any measure, and were not being aimed at specific trees. BT MG ammunition would need to be very powerful indeed - and we are talking tens to hundreds of MJ per trunk to explode substantial trunks into steam at the point of impact.

Not however, by any "daisy cutter" effect. That's just your delusion.

Exploding trunks into steam is not as efficient as a daisy cutter bomb, which primarily does blast damage. It seems fairly clear that the Locust there pumps multiple gigajoules of energy into the stand of trees.

The coefficient of static friction generally exceeds the coefficient of kinetic friction. Thus, a jolt that is sufficient to cause an object to start sliding may cause it to lurch downhill, regardless of the direction of the jolt.

Quit your bullshitting Spock. You claimed it was pushed downhill and was therefore not that impressive. I asked where you got that impression. You tried to back that up by claiming that Conner said it got pushed downhill when he didn't.

The tank did not get pushed downhill, so quit the bullshit. [/quote]
I recommend you re-read what I said. Carefully. As I said, there is absolutely no reason to conclude similar momentum for the round itself as the BT gauss rifle, and multiple good reasons not to.

In saying that, relative to the Conqueror, it has inferior fire-on-the-move capability.

How can you keep being this stupid? Lets pay attention to the quote shall we?

The AT83 Brigands, larger than their more primitive cousins the 70s, were, on paper, the Urdeshi forge world's equivalent of the Leman Russ. They had auspex guidance, weapon stabilisers and torsion bar suspension. They were the Blood Pact's best battle machines, not counting the very few ancient super-heavies they had inherited from defeated Guard units."

Which does absolutely nothing to show your point. The Conqueror tank is a Leman Russ variant.

It's a very flexible incident that can be modeled in a variety of ways.

Read As: I'm going to try to bullshit like crazy in an attempt to low ball it. But this isn't even remotely the end of your falsehoods.

No. The PPC strike in Close Quarters is also a very flexible incident as well. It's just that, unfortunately for you, even the least generous reasonable models fail to support it. The gauss rifle recoil incidents in and of themselves tell us almost nothing; they are also very flexible incidents - but they're perfectly compatible with our other information, and so support it.

It is a march across a wide open desert which happened to be beset by ambushes and raiders.

Man you are just plain dumb. The Imperials planned on a 20km a day advance. Slowed down by constant attacks, they slowed down to an average rate of 15km. This means that on foot and under constant attack, they managed to maintain a daily rate of advance only half of that of the entirely mechanized Invasion of Iraq.

20km a day is a reasonable rate of advance (especially with typical British "pull forward a bit and consolidate"), you just don't know a Mauser rifle from a Javelin.

All of which the Imperial plans did not account for in their "ambitious" plan to march 20 km per day across the desert and then meet the Tau in a pitched battle.

Bullshit again.

De Stael's offensive timetable called for the Tallarn regiments to make an ambitious twenty kms a day, but he expected that in some sectors along the front the Tau would stand and fight and that sector would naturally be slowed down or halted by combat. If the Tau committed their forces to battle in one sector, then others sectors would be able to move faster. De Stael's staff believes an average of twenty kms a day should be sustainable, especially as the Tallarn units would be operating in a familiar environment.

De Stael expected combat along the way. It was part of his insanely stupid plan that there would be heavy fighting in certain sectors and that everyone else would slip by.

Or, in other words, that most of the army would be unopposed at any given time while the Tau concentrated to stand and fight in some sectors.

No, I'm still not impressed by the marching speed of the Imperial Guard. It may be good for an infantry-based force that's only partially mechanized and towing heavy artillery pieces with sharply limited supplies of fuel and water, but it's not going to be good when you're facing BattleMechs.

There's also the Guardsmen in the advance being utterly surprised when they didn't meet any resistance the first day, the fact that they started off the advance with a full creeping barrage and hit likely places the next day.

Didn't meet any resistance... and still didn't go all that far.

The Imperium's logistical problems in the Taros campaign, moreover, display limitations on the Guard's common levels of mobility.

Not really, since Taros was atypical. First of all, the 13th Black Crusade was on. That massively sapped logistics as they were sending almost everything they could spare at it. They could barely get men to send there, much less supply them well.

Not to mention political matters and utter, utter stupidity on the part of Gustavus and De Stael.

Plus they always have to gimp the Guard due to the canonical fact that the Tau don't stand a chance in a full scale war against the Imperium. ;)

Let's give you a few excerpts from the BattleTech Techmanual to hammer home precisely what sort of logistical disadvantage Guard forces are at:

Because a MechWarrior might be in his cockpit for days at a time (and in the field for weeks), most BattleMech cockpits provide some storage lockers for rations, field gear, a personal firearm and other gear.

BattleMechs can and do operate for weeks out in the field with minimal logistic support; a MechWarrior is expected to be able to live out of his cockpit for days without being able to get out. The main supply issue for BattleMech? Ammunition for those times which you actually are engaging enemies.

Speaking of seats, many Inner Sphere BattleMechs provide one other seat in the cockpit: a foldout toilet... Without a storage tank to overflow, the endurance limit on cockpit toilets is how much toilet paper the MechWarrior has. Go ahead and laugh.

Yes, they really do deploy for very long missions with minimal logistic support. Did you remember to pack enough rolls of toilet paper, MechWarrior Thanatos? Well, you have to sleep sometime.

Indeed, some BattleMech cockpit designs go so far as to include a full ejection seat for the passenger and even provide them with some controls, such as communications systems.

Oh, wait, although you only need one person to drive it, most of them come with a passenger seat for those times when someone has to be awake to watch the sensors at all times.

Life support cannot spare the mass for unlimited air and water recycling, though it can operate anywhere from a few hours to several days in vacuum depending on the design. If air or water exists outside the 'Mech, however, the life support system can provide fresh oxygen for an almost unlimited period as long as the fusion engine runs.

Several days in the vacuum for some designs? Ok, so what about fuel?

These types gradually lost ground to protium users.

Oh, protium-fueled fusion. So you can use water?

This is why most military fusion engines include a small electrolysis unit to extract hydrogen for water. Those tales you may have heard, of MechWarriors “refueling” their BattleMechs with urine? Those aren't myths.

OK, so the Leman Russ can be fueled with anything combustible, and lasgun power packs can be recharged by building a wood fire on top of them, but a fifty foot war machine that can be powered by one guy pissing in a cup?

Face it: The Guard, as good as they are at scrounging fuel and power, are at a logistical disadvantage. BattleMechs are simply unreal here, just as they are in their terrain-handling abilities.

You might want to provide a quote to back up any claims about that.

With pleasure:

Heedless of the 105mm shells tearing into the highway and trees around him, Sirus confronted the Infardi armour head-on. The Wrath of Pardua sped forward with a clank of treads and fired its main gun. The hypervelocity round hit the nearest of the two enemy vehicles, exploding into the rear mantlet of its turret with such forcec the entire turret mount spun round through two hundreds and ten degrees. The tank clearly retained motive power, because it continued to churn along the road, but its traverse system was crippled and the turret and weapon swung around slackly with the motion.

An AT70 lobbed a shell at the Wild One that tore away its sponson and part of its track skirt. Another hit the Demands With Menaces on the turret destroying its vox-mast, pintle mount and laser range-finder, and killing the assistant gunner with explosive spalling.
Wounded but not down, the Demands With Menaces plunged forward, laying its guns at the Reaver responsible. Corbec saw the top-hatch pop and the commander emerge, oblivious to the danger, to verify aim with a handscope now his range-finder was junked.
He knew his job. The Demands rolled to a halt and jolted hard as it fired, jerking plumes of accumulated white dust off its surfaces and hull grooves like sifted flour. The sound of the hypervelocity AT shell was just a crisp, flat clap in the augmented air. The AT70 made a much fuller and more satisfying sound as it exploded.

If those are both Vanquishers, that's perfectly compatible with everything I've already said. If the first is actually a Conqueror, it does suggest higher than Mach 5 velocity for the Vanquisher's higher-speed AT rounds.

However, we still face the issue of momentum, and the Conqueror's rounds - and Vanquisher's rounds - still should have substantially less momentum than the Earthshaker, whose muzzle velocity is established and repeated in a very consistent fashion from 2003 onward in IA books, and will probably continue to be repeated in similar fashion as long Warwick Kinrade and/or Tony Cottrell continue to write for Games Workshop.

If the Vanquisher has the same recoil energy as the Earthshaker, is (6.5/9.0)^3 = 38% of the mass of the much larger gun based on barrel length ratios, and fires a subcaliber sabot ten times as fast as the Earthshaker round (> mach 20 - very high velocity), we're talking 2.3 kg exiting the barrel. Under the same conditions and a Mach 10 projectile, 5.6 kg. 10 kg? 1900 m/s. Start to sound familiar? It should. We're pretty much back where we started.

Sound better than the M829A3? Higher energy, yes. The larger cross section and lack of stabilizing fins make it a little less accurate and a little less efficient at the armor-piercing game, so it's a more primitive design even as it has a clear edge in destructive effect. It is still much closer to battle armor mounted gauss guns than BattleMech mounted gauss guns when we capture it on the BT scale of things.

Think about it carefully. We're dealing with small hypervelocity projectile - Tau railguns and Vanquisher AT rounds - that do fantastic at piercing Warhammer 40,000 armor, and you're suggesting that those same tanks that get killed so easily by those hypervelocity projectiles have a more than miniscule chance of surviving the impact of a hypervelocity projectile over ten times as big.

And in turn, are threatening to the giant war machines that can very often take hits from such weapons without suffering any reduction in combat effectiveness.

Well then you fucked up your math.

I suggest you probably made an error in calculation. Did you use the volume of a simple cylinder? That would account for close to a 30% error on your part. DU is 19.05 g/cc; tungsten is 19.25 g/cc. They're 1% apart in density, not 30%.

By all means, if you have calculations, show them. I remain unimpressed so far, and see no reason to discard the equivalences stated explicitly in the Imperial Armour series.

*sigh*
Effective thickness is the relative thickness based on the angle of the slope of the armor. I used the Imperial Armor figures for them when I calculated the thickness, so they're not going to contradict them are they?

So why mention them at all if they don't help you?

*beats head against desk*
Its. Not. The. Road. Speed.

It can be the speed, if that's low enough.

Sweet Jesus, you think that's a bad thing it can't do a full rotation in under a second?

Not really a bad thing per se. That's the absolute limit on the peak rotational speed of 2pi radians per second, i.e., when you sit there and spin up to peak rotational speed. You still must accelerate up to that speed and brake from that speed to a stop, so that maximum rotational speed is an upper limit that, in an ideal world, starts to affect turning performance when you go pi radians per second. If you turn with one tread, pivoting on a stationary tread, that speed limit affects any rotation averaging any less than pi/2 radians per second (a ninety degree turn in one second). Compared to a split-second 180 degree human-like turn, that is inferior; not necessarily bad, just not as good.

When we look at the fundamentals, the horsepower/mass ratio disadvantage, and having limited selection of force vectors (forwards and reverse on two parallel treadlines rather than vectoring meganewtons through a three-jointed hip-knee-foot limb), are what fundamentally make for less nimbleness in changing directions.

Back up your claim, Thanatos.

Easy.
The vehicle weight, listed speeds, crew duties, loading mechanism, completely different internal arrangement, etc.

Ah, but wouldn't that simply mean these are different patterns of Leman Russ Demolishers? This would seem a good standard practice for dealing with the numerous minor variations in published specifications.

As I said at the start, BattleTech battle armor are a fair match for Warhammer tanks. They can survive 'Mech grade weapons:

Thanks to the wonders of the chassis and super-strong myomers, battlesuits can carry far tougher armor than anything you've used before. With this stuff – and a bit of luck – you can survive BattleMech laser fire, missiles, autocannon shells and PPC bolts. Don't get cocky, though; even some punk from a planetary militia can drop you with a bolt-action rifle if he hits you just right.

They can match light 'Mech grade weapons, which in turn match Warhammer main tank weapons:

The net results are guns that can match their BattleMech equivalents.

They even match them in speed in many cases, with effective speeds ranging up into the 30 kph range, and are smaller targets that handle difficult terrain better.

Against a full bore BattleMech of equivalent tonnage? The basic 60 ton Dragon completely shreds the basic 60 ton Leman Russ and survives attacks that would obliterate them on a glancing hit, while exceeding the speed of the Salamander scout vehicle off-road and requiring less logistic support.

[Thanatos]

The Siege of Vraks, which reiterates and reinforces the 15-16 km effective range under roughly T-normal conditions, came out in late 2007, while the incident you reference comes from 2005.

That's not the way it works at all. New overwrites old is for use generally with the really old stuff or stuff that's out of print.

Potentially different types of canon

Oh this is rich.

however, that it exists in both types of canon means that it's a stronger example for it.

The different kinds of canon you just created. Maybe I should whip up some new types of canon too?

Note, further, that it's the normal range, and that they have available for the towed Earthshakers the "extreme" range option of using charges 6-7.

Except that you can only use 6 or 7 charges a handful of times before the gun is retired. You're not doing that on day one of 60.

Objects fall ~9% faster on Vraks.

Ignoring that its the wrong planet, that's not how gravity and projectiles work.

And?

I point out that you can't use it for quantification because there's basically nothing there to use to quantify it, and you don't know why thats a problem?

If you don't care to take my word for the fact that force dot distance gives the work done on an object

Actually, your "word" was that it was force times length of barrel rather than force times displacement. You tried to use barrel length as the displacement, when the recoil distance is what you would use if you were stupid enough to think you used Work to determine recoil.

What I'm describing is a basic law of kinematics, taught in just about every introductory physics course.

Sadly, you utterly fucked it up. The question is whether it was honest stupidity, or an attempt at dishonesty. More likely the latter given what we have seen.

No, I'd stopped bothering to look at the game mechanical descriptions at that point, as you seemed impervious to game-mechanical arguments.

Because they're not canon and as we'll see a bit later, you still are using them.

At long last you provide evidence for lascannon causing collateral damage

At long last, someone brings forward any evidence of the secondary effects!

In fact, the infantry case, closest to quantifiable, we see no evidence of ignition of the infantry or partial or full vaporization.

Actually there is evidence of ignition, I just left it out because it was vague.

If we assumed that the blast was 1 km/s debris with enough momentum to launch 100 kg/m^2 at 10 m/s at 5m, and that half the energy was released in blast form and half in radiant heat, both omnidirectionally (i.e., including into the ground), that would be 314 megajoules.

If you decide to set it up that way and then use the secondary effects yield as the primary yield.

We also have its lack of in-game blast effects

So you use in-game effects again after you claim you weren't using them anymore. Forget about the Fire Prism that you said had no effect on group targets? You're really incompetent at dishonesty.

This is ignoring the fact that lascannons and melta weapons don't effect multiple targets for game balance reasons. You can wipe out whole groups of men with a Melta, but you can only use it on a single target in game.

The lascannon is the secondary weapon of the Leman Russ

Piss easy to expain: Cannons are fantastic multipurpose weapons. There's something like 10 different types of rounds in service for it.

That's ignoring the fact that there are Leman Russ variants with lascannon main guns.

The primary weapon, the Battle Cannon, is less powerful than the Earthshaker

I remember when you posted the evidence that....wait, no you didn't.

which per the previously quoted passage in Honour Guard, has a ~2 GJ HE bursting charge and therefore generally nails a target with about a gigajoule on flat-surface impact.

Basic physics ignorance alert: They do damage through different methods.

we have the hellgun powerpacks and hellgun/lasgun effective yields vs nominal consumption levels

Ah yes, where you first assumed it used a lasgun pack because of some shitty online article, and then assumed that despite all evidence to the contrary, a hellgun pack was the same size as a Lascannon pack.

Eighth: You've had about a month to come up with some kind of quantifiable lascannon event pointing to >2 GJ yields, and haven't come up with a single one.

I haven't had even remotely the time to do any research. Even then, I not only used the source you gained by flat out cheating to give higher yields than 2GJ but also gave evidence of secondary effects.

You have been specifically asked for examples of the Lascannon not doing the level of secondary effects you imagine it should. You have not provided any.

You've been given even longer to give where you got your original estimate of 2GJ. You have only given examples of things you have found since then, so we can safely conclude your original estimate was purely ass pulled.

In fact, out of the 7 total things you list that "support" your conclusion, two came from me, one you got by cheating, and the rest are wild assed conjecture. You have provided no evidence (conjecture is not a type of evidence, even if Lionel Hutz says it is) of your own and you claim I've brought nothing forward when you used two of the sources I quoted?

Man, you really suck at this.

It's not a small laser; it's a medium laser

My mistake, though that actually makes things worse for BTech.

the same class of weapon seen causing tree trunks to explode in steam (as an unintented fringe effect) in the same battle:

Fringe effect my ass, those are direct impacts.

We're not talking about chopping down a tree in one minute with a carefully aimed burst; we're talking about levelling an entire grove in frenzied seconds while Cassie, IIRC, runs to a carefully prepared mudpit nearby to lure it in.

We're talking about 20mm MGs here, they'll cut down a tree in a few shots.

It seems fairly clear that the Locust there pumps multiple gigajoules of energy into the stand of trees.

No its not, not only do you have 20mm fire going into them, but its been established that it can cut down a tree per shot with the medium laser. That's aside from the fact that you never quantified the tree or the number of trees destroyed or even the time frame.

I recommend you re-read what I said.

I recommend you just quit lying. You claimed it wasn't impressive because it moved downhill. That has now been established as a flat out lie.

Which does absolutely nothing to show your point. The Conqueror tank is a Leman Russ variant.

Except for the tiny little fact that there are no Conquerors there and all variants are called by their variant name solely. Leman Russ Conquerors are called Conquerors, Leman Russ Vanquishers are called Vanquishers, Leman Russ Demolishers are called Demolishers, etc.

If its called a Leman Russ, is a Leman Russ. Nice attempt at bullshitting, but it utterly fails if you have even glanced at a 40K work. They were referring to the base pattern Russ.

In fact, the only source that says that only the Conqueror can fire on the move, is the original pre numbered Imperial Armor. Odd that you think a book from 2005 is overwritten by one that is from 2007, but one from 2000 should count more than the currently printed one.

Why, that would just be more rank dishonesty wouldn't it? How completely unsurprising.

it's not going to be good when you're facing BattleMechs.

Didn't meet any resistance... and still didn't go all that far.

They stopped and dug in every day in typical British fashion and they were combat advancing. They expected to be attacked any minute the whole way.

BattleMechs can and do operate for weeks out in the field with minimal logistic support

Wow, it described the inside of any vehicle ever. I'm so impressed!

Especially since Imperial vehicles have operated in the desert

Oh, wait, although you only need one person to drive it, most of them come with a passenger seat for those times when someone has to be awake to watch the sensors at all times.

Its almost like they knew the severe disadvantages of the one person ground vehicle you bragged about! Almost.

OK, so the Leman Russ can be fueled with anything combustible, and lasgun power packs can be recharged by building a wood fire on top of them, but a fifty foot war machine that can be powered by one guy pissing in a cup?

Doesn't actually tell us the requirements for full operation and how much good pissing into it does. Pissing in it (~30 oz if he's hydrated, I've had to piss into a lot of gatorade bottles in my time) could provide enough power to keep the aforementioned air recyclers running but not be remotely enough for motivation or weapons.

You'd have to know the reactors tank capacity and the efficiency of the electrolysis unit to get an idea of how much that's going to give him. I could put a cup of gasoline into my engine and get down to the gas station on the corner but its not going to get me down to my job.

Face it: The Guard, as good as they are at scrounging fuel and power, are at a logistical disadvantage.

Not really, since you have shown that the mechs have lower logistical requirements, not that they have better logistics.

You've given nothing on how well they can keep them supplied, which is what logistics is. Situations like Taros are in the minority, because they had to undercut the Guard like they always do whenever the Tau are involved.

They often can and do supply millions of men and vehicles for months with what they brought with the task force.

If the first is actually a Conqueror, it does suggest higher than Mach 5 velocity for the Vanquisher's higher-speed AT rounds.

It is.

If the Vanquisher has the same recoil energy as the Earthshaker

There's nothing to suggest that at all. So we can safely ignore this.

Especially since you don't know how recoil works.

So why mention them at all if they don't help you?

You're the one who brought up effective armor thickness. It told you I was quite aware of it.

Ah, but wouldn't that simply mean these are different patterns of Leman Russ Demolishers?

No, as different patterns than standard are specifically stated to be such.

This would seem a good standard practice for dealing with the numerous minor variations in published specifications.

Actually no, because you were a)using its performance for Leman Russ variants in general and b) This is where you use new overwrites old since its an out of print source.

They can survive 'Mech grade weapons

When the words "whole lotta luck" are involved, its generally safe to say that its almost certain that they generally can't.

The basic 60 ton Dragon completely shreds the basic 60 ton Leman Russ

I remember when you quantified the AC\5 on it.

Oh, wait. You didn't. You kept talking about how great the gauss gun was and provided nothing on the AC\5. Then all you provided on the medium lasers was that they could cut down a tree in a single hit.

And basically nothing on the LRM.

Not much qualification at all on the equal tonnage vehicle you selected.