Lasgun Firepower Split.

[18-Till-I-Die]

10mj? Thats all?

Thats odd cause Imperial Lasguns from 40k are outright stated to clock in at 20-30 megajoules. And they arent even considered that powerful in 40k (compared to plasma weapons or meltas, which are considered massively powerful by comparison).

Excuse the off topic i just find this interesting for comparison. I wasnt aware the difference was so high, thats three times more powerful.

[Lord Zentei]

10mj? Thats all?

Thats odd cause Imperial Lasguns from 40k are outright stated to clock in at 20-30 megajoules. And they arent even considered that powerful in 40k (compared to plasma weapons or meltas, which are considered massively powerful by comparison).

Excuse the off topic i just find this interesting for comparison. I wasnt aware the difference was so high, thats three times more powerful.

Where is the 20 megajoule figure from?

[18-Till-I-Die]

10mj? Thats all?

Thats odd cause Imperial Lasguns from 40k are outright stated to clock in at 20-30 megajoules. And they arent even considered that powerful in 40k (compared to plasma weapons or meltas, which are considered massively powerful by comparison).

Excuse the off topic i just find this interesting for comparison. I wasnt aware the difference was so high, thats three times more powerful.

Where is the 20 megajoule figure from?

As far as i know, the Imperial Guard fluff itself says it's rated at 25 "megathules" which has been taken, here by other threads and such, to mean "megajoules".

[Lord Zentei]

10mj? Thats all?

Thats odd cause Imperial Lasguns from 40k are outright stated to clock in at 20-30 megajoules. And they arent even considered that powerful in 40k (compared to plasma weapons or meltas, which are considered massively powerful by comparison).

Excuse the off topic i just find this interesting for comparison. I wasnt aware the difference was so high, thats three times more powerful.

Where is the 20 megajoule figure from?

As far as i know, the Imperial Guard fluff itself says it's rated at 25 "megathules" which has been taken, here by other threads and such, to mean "megajoules".

Well, I can safely say that that is horseshit. First off, it's 19 "megathules", and secondly, why the flying fuck is a "thule" = a "joule"? Why not a foot-pund? Hell, why not a teraton while we're at it? Apples and oranges! These are different goddamn units.

A modern rifle round is in the kilojoule range. And people in the Imperium still make use of goddamn autoguns for fuck's sake.

[18-Till-I-Die]

Where is the 20 megajoule figure from?

As far as i know, the Imperial Guard fluff itself says it's rated at 25 "megathules" which has been taken, here by other threads and such, to mean "megajoules".

Well, I can safely say that that is horseshit. First off, it's 19 "megathules", and secondly, why the flying fuck is a "thule" = a "joule"? Why not a foot-pund? Hell, why not a teraton while we're at it? Apples and oranges! These are different goddamn units.

A modern rifle round is in the kilojoule range. And people in the Imperium still make use of goddamn autoguns for fuck's sake.

Its not only that though, if i recall. I'm not the best one to make this case, but if you want i could look and see what has been said in other threads and i could PM you or start another thread (i dont want to derail the current one).

[NecronLord]

Split time. Stand by.

[NecronLord]

Megathules are almost certainly megajoules (comparatively, watts is a unit of measure in 40K). There are various descriptions of lasguns having appropriate effects, most notably wide scale pulverisation and explosive destruction of a human chest in Black Library pubications. These are consistant with shots in the 19 Mj range. Compare, if you will, with a lower limit for necron gauss gun firepower, which is several hundred megajoules.

Further, all instances of lower firepower should be explained as power settings, just as in SW debate, where this excuse is used to rationalise piffling examples of firepower like Leia's burnt arm.

A modern rifle round is in the kilojoule range. And people in the Imperium still make use of goddamn autoguns for fuck's sake.

1. So what? We have no idea what precise form autoguns take, they do in fact, vary greatly, according to all sources. Some as primative as single shot frontloading matchlocks, some more advanced than anything around today.
2. People in the Imperium make use of swords. Therefore no one in the Imperium should be able to have a laser gun. It's a highly diverse society, with highly diverse technologies available across it.
3. You betray ignorance by presuming energy content to equal damage. Kinetic impact is, joule for joule, vastly, and I do mean vastly more damaging than laser-style energy transfer. Rocks on Stormtrooper heads ring a bell?

[Lord Zentei]

Split time. Stand by.

Ah, sorry about that.

Its not only that though, if i recall. I'm not the best one to make this case, but if you want i could look and see what has been said in other threads and i could PM you or start another thread (i dont want to derail the current one).

Well, seeing as we have a thread split, let's have those links.

[NecronLord]

I didn't say I'd provide the links, but I may as well:

Firstly (finding these is a bit of a problem), we'll have a link talking about what a more formidable guardsman-level weapon can do. The horrid power of the meltagun

I will note that this figure is backed up by necron warriors being totally destroyed by this melta, wheas a 15 GW laser didn't destroy them in Deus Ex Mechanicus.

[Lord Zentei]

Megathules are almost certainly megajoules (comparatively, watts is a unit of measure in 40K). There are various descriptions of lasguns having appropriate effects, most notably wide scale pulverisation and explosive destruction of a human chest in Black Library pubications. These are consistant with shots in the 19 Mj range. Compare, if you will, with a lower limit for necron gauss gun firepower, which is several hundred megajoules.

Do you have the calcs for that?

People in the Imperium make use of swords. Therefore no one in the Imperium should be able to have a laser gun. It's a highly diverse society, with highly diverse technologies available across it.

That was not my argument.

You betray ignorance by presuming energy content to equal damage. Kinetic impact is, joule for joule, vastly, and I do mean vastly more damaging than laser-style energy transfer. Rocks on Stormtrooper heads ring a bell?[/list]

I made no such presumption. And yes, I remember that scene, all right. But we are talking about four orders of magnitude here.

[NecronLord]

Do you have the calcs for that?

For the Gauss Flayer? Somewhere. I suspect it would in fact be easier to re-do them, so I'll do that shortly.

I made no such presumption. And yes, I remember that scene, all right. But we are talking about four orders of magnitude here.

And? A low power lasgun shot still kills, full power, 19 Mj shots are used for punching through walls (Cityfight) or fighting huge beasties and so on, which Guardsmen come across reasonably often.

[Lord Zentei]

Do you have the calcs for that?

For the Gauss Flayer? Somewhere. I suspect it would in fact be easier to re-do them, so I'll do that shortly.

I made no such presumption. And yes, I remember that scene, all right. But we are talking about four orders of magnitude here.

And? A low power lasgun shot still kills, full power, 19 Mj shots are used for punching through walls (Cityfight) or fighting huge beasties and so on, which Guardsmen come across reasonably often.

No, I meant the lasgun calcs.

And modern firearms punch through walls and can kill elephants. You don't need fucking megajoules to do that.

[NecronLord]

The heat of vaporization of water is about 2260 kJ/kg
Lower end weight of an average healthy adult human male¹ is 121 pounds (54.88 Kg)
To vapourise him therefore, we need: 2260Kj*54.88 = 124,028.8 Kj
Gauss flayers are consistantly described as vapourising humans completely (and bear in mind, we're assuming humans are composed only of water here, melting and then vapourising bones would be a higher energy) in a second or less. In fact, they vapourise space marines and their armour in roughly the same time.
That means that the minimum wattage is 124 MW. In actuality, ordinary humans tend to be vapourised in "a heartbeat" or "an eyeblink" which implies even higher wattage.

¹ Source: USCDC publication

[NecronLord]

And modern firearms punch through walls and can kill elephants. You don't need fucking megajoules to do that.

You do with an energy weapon. Seriously, how do you think multi-megajoule blaster power is calculated, eh? I will look.

[Lord Zentei]

The heat of vaporization of water is about 2260 kJ/kg
Lower end weight of an average healthy adult human male¹ is 121 pounds (54.88 Kg)
To vapourise him therefore, we need: 2260Kj*54.88 = 124,028.8 Kj
Gauss flayers are consistantly described as vapourising humans completely (and bear in mind, we're assuming humans are composed only of water here, melting and then vapourising bones would be a higher energy) in a second or less. In fact, they vapourise space marines and their armour in roughly the same time.
That means that the minimum wattage is 124 MW. In actuality, ordinary humans tend to be vapourised in "a heartbeat" or "an eyeblink" which implies even higher wattage.

¹ Source: USCDC publication

Yes... but I was asking about the lasguns.

[NecronLord]

As I said, I am looking for old calcs. Just out of curiosity, why do you find it so hard to credit, given that a not-much-bigger melta is able to store, contain and utilise energies over a thousand times more powerful than 19MJ/shot?

[Lord Zentei]

As I said, I am looking for old calcs. Just out of curiosity, why do you find it so hard to credit, given that a not-much-bigger melta is over a thousand times more powerful than 19MJ/shot?

Impression received from casual reading. I'm entirely prepared to accept it if a concrete calc can be found, mind.

[Azazal]

Well, seeing as we have a thread split, let's have those links.

Hey Lord Z, no links but here are some fluff examples of lasguns in action.

1. From "Nightbringer", page 220 - "Danil Vorens lowered his smoking laspistol and returned his attention to the viewscreen before him. A stunned silance filled the defence control room, the technicians agog at what had just happened. Lutricia Vijeon stared in open mouthed hoor at the corpse lying in the center of the room with a ragged hole where its face had been."

2. "Nightbringer" again, page 230/231 - " Almerz Chanda stood over the body of the palace guard, expertly holding a smoking lasgun. He snapped off a shot at Barzano, taking the inquisitor high in the sholuder and slammin him back against the shuttle's hull. Brazano yelled in pain and dropped his weapon." Few paragraphs later "Barzano tried to ignore the pain of the laser burn on his
shoulder."


3. "Storm of Iron" , page 208 - "Hawke fired a hail of las-bolts, ripping the man's chest to bloddy ruin"

4. "The Inquisition War", this is the trilogy reprinted into a single volume, page 282 - "laser pulses flashed from the high gallery cloaked in deepest shadow. Air and dust ionized to a brilliant green. The pulses hit books, melted brass, setting permaparchment ablaze."

5. "The Inquisition War", page 550 - "The bolt impacted. It tunnelled and exploded. Flesh and bone or a vital organ erupted. It was ever this roudy way. By contrast, laspistols were silent in operation. If the aim was inaccurate, the scalpel-blade of energy soon dispersed. Whener a las-pulse met its target: such lacerating flare-up, such a scream of agony, if the victum still had the breath and lungs and heart to scream. Perhaps ten of the pilgrams had fled. A score more lay dead or dying, almost all thanks to the laspistols."

6. "Warhammer Wargear, 2nd Ed", page 29 has a guardsman with a lasgun - "He snapped off a shot at the charging Ork, catching it in the arm. It ignored the wound as if it felt now pain."

And modern firearms punch through walls and can kill elephants. You don't need fucking megajoules to do that.

You do with an energy weapon. Seriously, how do you think multi-megajoule blaster power is calculated, eh? I will look.

Actully I would like to know as well. I have never seen nor heard of a person being hit by a MJ level energy or beam weapon in real life, as such I have no frame of referance on what the effect would look like other then massive tissue damage caused by water being vaporized.

[Lord Zentei]

Nice quotes Azazal, though a little hard to quantify by.

[NecronLord]

Gah. I distinctly remember this coming up many times before. When I look for it... nothing.

Anyway, a sub-megajoule laser, and what it would do is described here. As you can see, this is far too weak to be descriptive of what a lasgun does. Lasguns do more than just generate burns. You're definately into single figure megajoule ranges, if nothing else, from lasguns being able to instantly-kill humans and seriously fuck bits of their anatomy up.

[Lord Zentei]

Gah. I distinctly remember this coming up many times before. When I look for it... nothing.

Anyway, a sub-megajoule laser, and what it would do is described here. As you can see, this is far too weak to be descriptive of what a lasgun does. Lasguns do more than just generate burns. You're definately into single figure megajoule ranges, if nothing else, from lasguns being able to instantly-kill humans and seriously fuck bits of their anatomy up.

No sweat, no need for hazzle on this. It can be dug up in due course, or recalculated. And that's an interesting site, I'll have to skim through it.

Though there is one point I'd like to consider: flash vapourization could conceivalby deliver additional incidental damage to flesh. Flash vapourizing the water in a section of flesh will cause the nearby flesh to be shredded by the sudden pressure, so if an energy weapon destroys such and such a volume of flesh that doesn't neccesarily mean that all of it was vapourized.

[NecronLord]

Indeed, that's what, as I recall, old estimates assumed was the source of the oft mentioend 'pulverisation' of human flesh in lasguns.

[Star-Blighter]

And modern firearms punch through walls and can kill elephants. You don't need fucking megajoules to do that.

Take an energy weapon (laser, maser, microwave-whatever) and a projectile weapon that have the same rough effect on a given quantity of material, and the projectile weapon will be vastly more efficient in terms of energy usage and waste heat simply because the projectile weapon is throwing a physical impactor with measurable kinetic energy and more importantly, momentum.

The laser on the other is emiting focused radiation and will have to burn through the material, dealing with material vaporisation that will cause beam scattering and the atmostsphere itself which will hinder the beam actually reaching the target with any appreciable focus.

And for the record, a shotgun chambered in 12 gauge and loaded with a one ounce solid slug has over 6 megajoules worth of kinetic energy using the time tested formula:


KE = 1/2 (M * (V * V))
M = KE / (V * V)
V = KE / (1/2 * M)

6.3 MJ = 1/2 (35. Kg * (600 * 600 M.P.S.))


Granted this will vary depening on load and barrel length but serves as a good average to go by. Megajoule-range slugthrowers are around, easy to get, have been around for a very fucking long time.

[Azazal]

Gah. I distinctly remember this coming up many times before. When I look for it... nothing.

Anyway, a sub-megajoule laser, and what it would do is described here. As you can see, this is far too weak to be descriptive of what a lasgun does. Lasguns do more than just generate burns. You're definately into single figure megajoule ranges, if nothing else, from lasguns being able to instantly-kill humans and seriously fuck bits of their anatomy up.

Damnit, work web filter won't let me see grumble grumble

Star-Blighter, might want to double check that math there

[NecronLord]

12 Oz is 0.340194278 KG.

Ke of 61,234 J at 600 M/s