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 Keep wrote:
to slice "even" through 300mm steel at range would require some serious high power laser IRL - something we can't achieve yet, at least not to my knowledge. Also "steel" - imperium uses plasteel, which could possess magical capabilities that we dont know of, which make it better then RL armored steel.

The text is quite clear, its steel, its meant to give us an IRL comparision, this argument can't be used.

HexHammer wrote:

 Melissia wrote:
Also, you have to keep in mind the user's ability to aim it, too. Most people cannot aim beyond a few hundred meters without computer assistance.

? What about scope? A las weapon doesn't have any arc or magnus effect, nor are disrupted by earth rotation, to my knowledge.

A scope doesnt help you see through smoke, fog, trees, or hills. You can rarely see too far on a battlefield.

Also, trained and skilled snipers aren't "most people". Most soldiers very rarely shoot beyond 100 meters. Infantry engagement ranges haven't changed since WWII-- even snipers usually fire only at targets within 300 meters. This is more a human limitation than a technological one. The most effective shooting shooting ranges for human infantry is around 25-50 meters or so.

 Mr_Rose wrote:

The thing is, the technology and mathematics to make las-weapons workable exists today, except for one thing: batteries.

There is nothing particularly extraordinary about the laser weponry that the studio describes except for the ridiculous energy density of their power packs, which is orders of magnitude higher than hydrocarbons.
To put that in perspective, if we had batteries that good now, we could build "brute force" hover cars with electric engines that used turbines for both lift and thrust, and still give them operating ranges of hundreds of miles; that's how insanely good lasgun batteries are.

A laser gun that has enough strength to burn/disable a human sure.
A laser cannon that heats up a tank to the point that it's mechanics lock up or it's electronics fail not a problem. Most vehicles are very prone to damage from heat, just not in the way we expect.

But a laser cannon that has the strength to 'punch through' a tank's armor cleanly no. At that point the problem is not just the batteries, but that you are throwing around so much energy that you are likely going to burn everyone on the battlefield. Using that much energy against a tank 300m away and some dust/water/air between the gun and the target is going to heat up to a plasma and burn you. Cooling the cannon would be an epic task.

 Exergy wrote:

HexHammer wrote:

 Melissia wrote:
Also, you have to keep in mind the user's ability to aim it, too. Most people cannot aim beyond a few hundred meters without computer assistance.

? What about scope? A las weapon doesn't have any arc or magnus effect, nor are disrupted by earth rotation, to my knowledge.

A scope doesnt help you see through smoke, fog, trees, or hills. You can rarely see too far on a battlefield.

That's strange, modern soldiers use thermal scopes, but in the far far future they apparently don't as things gotten worse.

Melissia wrote:Also, trained and skilled snipers aren't "most people". Most soldiers very rarely shoot beyond 100 meters. Infantry engagement ranges haven't changed since WWII-- even snipers usually fire only at targets within 300 meters. This is more a human limitation than a technological one. The most effective shooting shooting ranges for human infantry is around 25-50 meters or so.

I'd dispute that greatly. While I agree that a good chunk of modern engagement ranges against Insurgents will occur within 100m (Particularly in Urban areas), the average engagement range for your standard infantryman is generally closer to the 200-300m range. Furthermore, there are vast tracts of land between compounds in the likes of Afghanistan and Iraq that regularly require the infantry to engage targets even up to 400-500m. You certainly don't have to be a trained Sniper or DM to hit something at ranges up to that. Within the British Infantry, the routine range training for standard-issue L85A2 is up to 300-400m as standard. Furthermore, most optical sights such as the British SUSAT or the US ACOG are graded in the 100-600 ranges, specifically to enable engagement over these ranges. For a properly trained and equipped infantryman, it's not miraculous to hit anything out to 300-400.

I'd also dispute that engagement ranges haven't changed since the Second World War - even a quick Google will bring up a missive named 'Increasing Small Arms Lethality in Afghanistan', in which a US Officer is advocating change within the US battle-doctrine because they were finding engagement ranges had shifted closer to the 500m mark and training/equipment wasn't keeping pace. Of course, even Second World War ranges are disingenuous - house to house fighting may be as little as 3m ranges, but fighting in North Africa, the Eastern Front and Italy (Where terrain is either open desert/tundra/countryside or mountainous) would significantly increase ranges.

As for the engagement distance of a Sniper, I'd judge 300m to be more uncommon - or at the least common only within urban areas. For a sniper to be engaging at the same range as his assault rifle counterparts suggests that the sniper isn't making full use of his weapons system, or has become trapped in a disadvantageous position. The British Sniper's rifle, the L115A3, is specifically selected to allow (By their own words from the British Army website) ' the ability to achieve a precision shot at up to 400m, achieve a first round hit of a man size target at 900m and provide harassing fire out to 1500m.'

Similarly, US Snipers are required to be able to place 90% of their shots on a man-sized target at 600m, again on the first shot. The longest kill ever confirmed was at 2,430m by British Corporal of Horse Craig Harrison - although by his own admission, conditions were perfect for the two kills he made over this distance. However, it goes to show that if a sniper can consistently make shots over this distance (CoH Harrison took out a two man machine gun team in that engagement), then a 300m shot is by no means an extraordinary feat. Indeed, most civilian huntsmen I've come across regularly shoot at a 100-200m range simply due to the animal's (Deer) keener sense of smell and perception of motion.

one thing to keep in mind is that laser weapons won't have a solid range cap, and instead would have a gradual damage fall off, a laser weaspon REALISTICLY statted would be like S9 at 0-3 inches S8 and 4-12 inches and keep slowly falling off until it was eventually useless. realistiucly a lascannon would continue to be effective agaisnt say a rhino at a further range then they'd be vs a land raider

Actually Energy density is one of the biggest hurdle in a lot of engineering problems and the reason a great deal is infeasible at the moment. Hell think of all the crafts that can achieve lift off in sci-fi universes and compare that to energy needed to do so.

 Bobthehero wrote:
No, there's litteraly a page where Forgeworld goes ''the armor of a Land Raider is the equivalent of 300mm of steel'' almost word for word.

Indeed, the original FW manuals had steel thickness equivalents. Modern antitank weaponry would have gone through nearly all 40K vehicles like crap through a goose.

 Frazzled wrote:

 Bobthehero wrote:
No, there's litteraly a page where Forgeworld goes ''the armor of a Land Raider is the equivalent of 300mm of steel'' almost word for word.

Indeed, the original FW manuals had steel thickness equivalents. Modern antitank weaponry would have gone through nearly all 40K vehicles like crap through a goose.

and Melissa's point is that we should proably just roll our eyes and ignore that fluff. this is why one of my personal rules for writing sci-fi is NEVER give numbers like that.

I am not talking about her points, I am talking about people saying that they meant plasteel and that it probably has abilities we don't know about

HexHammer wrote:

 Exergy wrote:

HexHammer wrote:

 Melissia wrote:
Also, you have to keep in mind the user's ability to aim it, too. Most people cannot aim beyond a few hundred meters without computer assistance.

? What about scope? A las weapon doesn't have any arc or magnus effect, nor are disrupted by earth rotation, to my knowledge.

A scope doesnt help you see through smoke, fog, trees, or hills. You can rarely see too far on a battlefield.

That's strange, modern soldiers use thermal scopes, but in the far far future they apparently don't as things gotten worse.

still doesnt help you see through hills....

BrianDavion wrote:
and Melissa's point is that we should proably just roll our eyes and ignore that fluff. this is why one of my personal rules for writing sci-fi is NEVER give numbers like that.

Much like with the bible, you cannot take all 40k lore equally seriously because the various books that make it up contradict each other frequently. I argue for interpreting in a way that is most consistent, instead. But on both topics that makes people present me to be an donkey-cave

HexHammer wrote:

 rawne2510 wrote:

HexHammer wrote:
Then what does the SM have to compensate for range and power, according to fluff?

Imperial Guard

So they can just snap their fingers and they drop some Basselisks/Leman Russ? ..then why wouldn't SM have them in their arsenal to begin with?

They used to, I know leman russ variants used to be fielded by Space Wolves and Basilisks were fielded and crewed by space marines during the horus heresy, FW even do a model for them.

However the main reason Space Marines don't used tanks is because what is the point of creating super soldiers capable of wearing armour that is comparable to the tank's armour anyway (in the fluff at least), only to sit them at the back of the battlefield lobbing shells?

They may as well leave that to the Guard, especially when you're only operating at chapter sizes. It's the same reason that they don't equip the SAS with MBT's or Howitzers..... or equip tank crews with support weapons, mortars etc. It's not very efficient.

 Bobthehero wrote:

 Keep wrote:
to slice "even" through 300mm steel at range would require some serious high power laser IRL - something we can't achieve yet, at least not to my knowledge. Also "steel" - imperium uses plasteel, which could possess magical capabilities that we dont know of, which make it better then RL armored steel.

The text is quite clear, its steel, its meant to give us an IRL comparision, this argument can't be used.

Does the example say it's equivalent to angled or none angled armour? I seriously doubt I GW or FW writer bothered to go that in depth. They're sci-fi writers, I doubt there's any sense of realism with 'any' of the statistical data given in 40k's fluff whether it's do do with weapons, vehicle sizes, crew amounts, internals etc etc. We have guns 'now' that can pen 560mm at 2000m.

Comparable thickness also depends on 'what' is being fired at it. The original M1 Abrams had an equivalent thickness of 350mm RHA vs KE rounds or 700mm vs Shaped Charges. Also Plastisteel sounds suspiciously like a form of composite armour seeing the word combines plastic and steel, which is often the two main combinations.

TLDR version? The writers most likely didn't have a clue what they were writing about and possibly wanted to give the impression the imperiums AFV's are most likely inferior to what we're fielding now.

The old game Confrontation (to become Necromunda in time) had very realistic ranges for weapons (and a lot of just good information on the tech).

It gave lascannons max range as 2500". Take that as you will.

 Baldeagle91 wrote:


Does the example say it's equivalent to angled or none angled armour? I seriously doubt I GW or FW writer bothered to go that in depth. They're sci-fi writers, I doubt there's any sense of realism with 'any' of the statistical data given in 40k's fluff whether it's do do with weapons, vehicle sizes, crew amounts, internals etc etc. We have guns 'now' that can pen 560mm at 2000m.

Comparable thickness also depends on 'what' is being fired at it. The original M1 Abrams had an equivalent thickness of 350mm RHA vs KE rounds or 700mm vs Shaped Charges. Also Plastisteel sounds suspiciously like a form of composite armour seeing the word combines plastic and steel, which is often the two main combinations.

The M1 Abrams's 120 mm gun firing KE projectiles also has a incredible penetration against steel armor. More recent versions are well over 600mm, at a range of 2km. Up close it will go through over a meter.

And yet there are defenses against such things.

 Exergy wrote:

 Baldeagle91 wrote:


Does the example say it's equivalent to angled or none angled armour? I seriously doubt I GW or FW writer bothered to go that in depth. They're sci-fi writers, I doubt there's any sense of realism with 'any' of the statistical data given in 40k's fluff whether it's do do with weapons, vehicle sizes, crew amounts, internals etc etc. We have guns 'now' that can pen 560mm at 2000m.

Comparable thickness also depends on 'what' is being fired at it. The original M1 Abrams had an equivalent thickness of 350mm RHA vs KE rounds or 700mm vs Shaped Charges. Also Plastisteel sounds suspiciously like a form of composite armour seeing the word combines plastic and steel, which is often the two main combinations.

The M1 Abrams's 120 mm gun firing KE projectiles also has a incredible penetration against steel armor. More recent versions are well over 600mm, at a range of 2km. Up close it will go through over a meter.

And yet there are defenses against such things.

Well the main difficulty being accurately hitting things at that range... especially if your opponent is hull down. Even against older MBT's, most brand new MBT's are vulnerable to being penetrated, often relying on post penetration countermeasures to protect the crew.

It's akin to how the Coalition forces were worried about their tank losses vs the Iraqi's in the first gulf war. It never happened due to the tanks being older or export versions lacking the updated sights and targeting systems, meaning they were simply unable to accurately hit the allies at ranges the allies could hit them.

For a lot of the imperiums vehicles, even those used by space marines, a common theme is how performance is sacrificed for reliability, ease of production or being able to run on any fuel. Even then many vehicles were never originally designed a combat vehicles. Hell I have a feeling the Leman Russ was originally a tractor (whether or not an artillery or agri tractor I dunno) and everyone knows about the rhino of which most space marine vehicles have their chassis based on by the time you get to the 41st century.

 Bobthehero wrote:
No, there's litteraly a page where Forgeworld goes ''the armor of a Land Raider is the equivalent of 300mm of steel'' almost word for word.

O_O eh, 30 cm Imo that would qualify as medium armor, I dunno much about 40k fluff, so is it because it's a glorified transport? Modern tanks has about 1 meter of frontal armor, that mixed with ceramics and heavy isotope metals.


Automatically Appended Next Post:

 Baldeagle91 wrote:
They used to, I know leman russ variants used to be fielded by Space Wolves and Basilisks were fielded and crewed by space marines during the horus heresy, FW even do a model for them.

However the main reason Space Marines don't used tanks is because what is the point of creating super soldiers capable of wearing armour that is comparable to the tank's armour anyway (in the fluff at least), only to sit them at the back of the battlefield lobbing shells?

They may as well leave that to the Guard, especially when you're only operating at chapter sizes. It's the same reason that they don't equip the SAS with MBT's or Howitzers..... or equip tank crews with support weapons, mortars etc. It's not very efficient.

Because then their roles are extremely limited and doesn't really extend to other things than Navy Seals could do like needle point operations, and not pitched battles or prolonged multirole warfare.

As I understand it, a single chapter SM takes on hive fleets, Ork Wargs etc but that wouldn't make sense without heavy long ranged artillery. Modern artillery has easily a range of 40 km. Only thing I can come up with in their arsenal are orbital bombardment from their Battle Barge.

HexHammer wrote:

 Bobthehero wrote:
No, there's litteraly a page where Forgeworld goes ''the armor of a Land Raider is the equivalent of 300mm of steel'' almost word for word.

O_O eh, 30 cm Imo that would qualify as medium armor, I dunno much about 40k fluff, so is it because it's a glorified transport? Modern tanks has about 1 meter of frontal armor, that mixed with ceramics and heavy isotope metals.

Well the Landraider is supposed to be extremely heavily armoured...... seeing modern MBT tanks have the equivalent of 600mm-900mm of RHS... which is classified as 'medium' in modern classification..... so at 300mm that's pretty light. Then again the LR does have extremely flat sides. Modern armour is mostly, steel, metals, plastics and ceramics resulting in something that is physically around 50-30mm if I remember correctly, although one report states conscripts say the joints on the Leo 2 suggested a maximum of 80cm.... which having seen some of the welds on a leo 2 doesn't convince me in the slightest.

The wedge may be around 800mm LOS thickness, but the physical thickness of the upper glacis plate is closer to 40mm (which makes part of the wedge). Which is about right seeing 40mm would provide a simply LOS protection of 320mm at 7 degrees without being special at all. Seeing the wedge is in effect two plates and would be thicker, I can see how 800mm of LOS would be possible.

Once again TLDR version, the writer probably had no idea how thick the armour actually would need to be, to be classified as thick, so probably put 300mm as that would be high in comparison to ww2 heavy tanks.

HexHammer wrote:
Automatically Appended Next Post:

 Baldeagle91 wrote:
They used to, I know leman russ variants used to be fielded by Space Wolves and Basilisks were fielded and crewed by space marines during the horus heresy, FW even do a model for them.

However the main reason Space Marines don't used tanks is because what is the point of creating super soldiers capable of wearing armour that is comparable to the tank's armour anyway (in the fluff at least), only to sit them at the back of the battlefield lobbing shells?

They may as well leave that to the Guard, especially when you're only operating at chapter sizes. It's the same reason that they don't equip the SAS with MBT's or Howitzers..... or equip tank crews with support weapons, mortars etc. It's not very efficient.

Because then their roles are extremely limited and doesn't really extend to other things than Navy Seals could do like needle point operations, and not pitched battles or prolonged multirole warfare.

As I understand it, a single chapter SM takes on hive fleets, Ork Wargs etc but that wouldn't make sense without heavy long ranged artillery. Modern artillery has easily a range of 40 km. Only thing I can come up with in their arsenal are orbital bombardment from their Battle Barge.

Ohhh space marines do have 'some' artillery, but it an extreme waste of space marines to have them manning artillery. Medium ranged stuff like whirlwinds etc, which are actually long ranged but nothing on basilisks. Most of the time you'll see them take command of imperial guard regiments and support elements. Outside of the Horus heresy (where space marines did have their own basilisks), they're not going to be fighting without the imperial guard being present. On chapter worlds you actually will see unaugmented humans directly under the control of chapters, just look at the battles on Baal or Macragge, plenty of non space marine troops.

Space marines in the current fluff when they're chapter size are not actually suited for prolonged warfare or pitched battles. The Imperial Guard are the sledgehammer while Space marines are the scalpel. The only exceptions are when you see multiple chapters banding together, often successor chapters banding around a first found chapter, the extent they almost form a force large enough, if not larger, than the space marine legions of old.

 Baldeagle91 wrote:
Ohhh space marines do have 'some' artillery, but it an extreme waste of space marines to have them manning artillery. Medium ranged stuff like whirlwinds etc, which are actually long ranged but nothing on basilisks. Most of the time you'll see them take command of imperial guard regiments and support elements. Outside of the Horus heresy (where space marines did have their own basilisks), they're not going to be fighting without the imperial guard being present. On chapter worlds you actually will see unaugmented humans directly under the control of chapters, just look at the battles on Baal or Macragge, plenty of non space marine troops.

Space marines in the current fluff when they're chapter size are not actually suited for prolonged warfare or pitched battles. The Imperial Guard are the sledgehammer while Space marines are the scalpel. The only exceptions are when you see multiple chapters banding together, often successor chapters banding around a first found chapter, the extent they almost form a force large enough, if not larger, than the space marine legions of old.

Isn't it so that Basilisks has a higher cal? And WW doesn't really pack much of a punch on strongholds?

HexHammer wrote:

 Baldeagle91 wrote:
Ohhh space marines do have 'some' artillery, but it an extreme waste of space marines to have them manning artillery. Medium ranged stuff like whirlwinds etc, which are actually long ranged but nothing on basilisks. Most of the time you'll see them take command of imperial guard regiments and support elements. Outside of the Horus heresy (where space marines did have their own basilisks), they're not going to be fighting without the imperial guard being present. On chapter worlds you actually will see unaugmented humans directly under the control of chapters, just look at the battles on Baal or Macragge, plenty of non space marine troops.

Space marines in the current fluff when they're chapter size are not actually suited for prolonged warfare or pitched battles. The Imperial Guard are the sledgehammer while Space marines are the scalpel. The only exceptions are when you see multiple chapters banding together, often successor chapters banding around a first found chapter, the extent they almost form a force large enough, if not larger, than the space marine legions of old.

Isn't it so that Basilisks has a higher cal? And WW doesn't really pack much of a punch on strongholds?

Basilisks are 132mm.... which scale wise is completely wrong seeing the Russ only has a 105mm gun..... also a basilisk is obviously modelled on the German 8.8cm flak gun and the barrel is too long for it to be useful at indirect fire at anything other than longer ranges or from elevated positions, akin to how the allies repurposed tank destroyers in ww2 when the germans ran out of tanks..... but anyway I digress.

When correctly used in the fluff and using real life logic.... which admittedly the writers don't have.... the basilisk is used for two main roles. As a long range distruptor.... aka breaking up formations, pinning the enemy, forcing them into cover, harassing fire during an enemy advance, counter-battery fire to suppress enemy artillery and destructive fire at selected enemy units. It's not really suited to bombard heavy fortifications. It's need for direct fire to be accurate is also a weakness, as the range needed to fire indirectly is rather extreme. However as the US showed during ww2 this can be countered with great training, but even then howitzers would be prefered. The role GW tried to copy for the basilisk was ww1 heavy howitzers but gave it the look of the 8.8cm flak gun. It's second role would be direct fire support, which would mostly be on the defensive and mostly helping against enemy armour. This is supported by both the fluff and real life comparisons.

To take out heavy fortifications you'd use the shorter range 40k equivalent of heavy howitzers, heavy field artillery or field mortars (aka heavy mortars). This is what the Medusa would fill and is the most common variant used in this role(disclaimer other artillery is available). This is why the space marine legions originally were equipped with Both Medusa's and Basilisks when they still fought in pitched battles..

*However* now that space marines generally operate in much smaller numbers, they are effectively reduced to special ops. As such they rarely need artillery. If they need some they will usually commandeer them from the imperial guard, take some out of their old stocks that have been mothballed or use the Whirlwind and Vindicator. Now the Vindicator is used generally for removing bunkers, fortifications and the like in a direct support role. However the whirlwind is basically using for softening up an enemy or fortifications at the last moment before the main attack starts. You wouldn't necessarily expect them to take out the hardest of fortifications, but they are perfectly capable of destroying a wide range of fortifications, and due to their extremely good ability to fire incredibly indirectly (think javelin missiles) at extremely short ranges, they're incredibly accurate.

Maximum range under controlled conditions <> in-the-field range

We can assume that 40K armor has refractive unobtanium crystals, etc., that are factored into AV, in rough analogy to modern-day reactive armor on tanks.

But most importantly, it's the necessity of a playable game. I always laugh at BattleTech, where in spite of the long age of darkness and lost technology, people can repair and make proton accelerators. However, they can't figure out how to mount WWII-era gyrostabilizers or have targeting systems that account for the Earth's curvature, with the effect that Long-Range Missiles (not a description, the actual weapon's name) have an in-game range limit that's under 4 city blocks. But I'd pull out Panzerblitz if I wanted to play a game centering around off-board (well, adjacent strategic-level hex) artillery.

The first mention of recoil on laser weapons I remember is the article on the new devastator squad box ingtroduced in 3rd edition; the "sniper-style" lascannon has a recoil compensator according to Jes Goodwin's concept sketch.

Not totally useless, since photons have momentum - that's how solar sails work. Feel free to calculate how much energy a lascannon puts out in a single shot for a Marine to need a recoil compensator. I did it once, and the number was ... rather high. I can't remember my working now, though, or the assumptions I used about the mass of a Marine in armour or the imparted recoil momentum.

The quoted equivalent armour thicknesses in the old IA books were silly. If you took them as meaning an equivalent of modern RHA, then they were incredibly flimsy. But then that's contradicted by depictions of tanks taking hits powerful enough to push an entire Leman Russ tank back several feet without sustaining any actual damage to the vehicle.

Also, the original equivalent to the gun on an Abrams, Challenger, T-80 isn't a battlecannon; it's the autocannon (Rogue Trader rulebook, p82). Except in the 41st millennium it's (barely) man-portable.

 Exergy wrote:
still doesnt help you see through hills....

For the "painter" it does, a painter is a person with a laser that can point at the target and get a distance reading, so that the target are designated and the coordinates are transmitted to the gunner. Been so for over 3 decades irl.

HexHammer wrote:

 Exergy wrote:
still doesnt help you see through hills....

For the "painter" it does, a painter is a person with a laser that can point at the target and get a distance reading, so that the target are designated and the coordinates are transmitted to the gunner. Been so for over 3 decades irl.

And that is great if you have an indirect fire weapon. A lascannon on the other hand requires line of sight to hit something, or penetrating power to get through whatever is in between. A hill is likely going to stop a beam of light from passing through it and still having enough energy to kill a tank.

 Exergy wrote:

HexHammer wrote:
]For the "painter" it does, a painter is a person with a laser that can point at the target and get a distance reading, so that the target are designated and the coordinates are transmitted to the gunner. Been so for over 3 decades irl.

And that is great if you have an indirect fire weapon. A lascannon on the other hand requires line of sight to hit something, or penetrating power to get through whatever is in between. A hill is likely going to stop a beam of light from passing through it and still having enough energy to kill a tank.

SM does have a indirect weapon, like WhirlWind.

BrianDavion wrote:

 Frazzled wrote:

 Bobthehero wrote:
No, there's litteraly a page where Forgeworld goes ''the armor of a Land Raider is the equivalent of 300mm of steel'' almost word for word.

Indeed, the original FW manuals had steel thickness equivalents. Modern antitank weaponry would have gone through nearly all 40K vehicles like crap through a goose.

If I recall correctly, it simply said '...equivalent to n mm of conventional steel'. That doesn't tell us what the Imperium considers to be 'conventional steel'. It could well be something significantly better than what we think of as conventional steel. It also doesn't tell you whether that's the minimum armour or the maximum (which makes a huge difference, AFVs are not protected equally all over) or what it's protecting against (armour can only really be rated as equivalent to another material against a specific weapon; modern armour is often only a little better than steel against some threats and several times more protective against others. With the far larger and more exotic range of weapons in the 40k setting there's plenty of room for huge differences).

Heck, I'd even question if the Imperium's units of measurement are the same as ours. Is the 'mm' they mention actually a twenty-first century millimetre, some unit which is considered close enough to the millimetre for translation purposes or a completely different unit with a similar name? If we take the measurements given in 40k sources as being in the exact same units as we use there are an awful lot of (baseline human) people over seven feet tall in the novels...

Is Corporal of Horse Harrison that guy from the Old Spice ads?

It is mentionned that it is the front armor (generally the thickest armor, bar a few examples like the Minotaur), it also gives most of the techno-bable/made up materials that compose the armor, then gives the 300mm comparision.

As for the unit of measurement, you could make the same argument for pretty much every words considering the language wont be the same in far future, might as well pretend that the conventionnal steel meant wood and that up means down if we're going to twist language like that.

7 feet tall people exist today, no reasons they wouldn't be there in an Imperium so large.

HexHammer wrote:
SM does have a indirect weapon, like WhirlWind.

Which is nice and all, but we're not talking about the fething whirlwind. The thread is about the Lascannon.