Power of 40k infantry plasma weapons.

[The Reaper]

I dived behind the obelisk just as the plasma cannon recharged, and a searing bolt of star-stuff roared past
the glittering lump of ironmongery, finally expending itself in the lake beyond. A thousand litres of water flashed instantly into
steam, wreathing the whole scene in a chilling mist, which blocked out the sunlight as abruptly as a slamming door, and I began to
think we might have a chance after all.

Can anyone calc that?

And how does this compare to other universes power weapons.

[Raxmei]

Water's heat of vaporization is 2257 kilojoules per kilogram and a liter of water conveniently has a mass of 1 kilogram (thank you metric system). 2.26 gigajoules to boil off a thousand liters, not counting temperature change. Less energy than a melta, more than a lasgun.

[The Reaper]

Water's heat of vaporization is 2257 kilojoules per kilogram and a liter of water conveniently has a mass of 1 kilogram (thank you metric system). 2.26 gigajoules to boil off a thousand liters, not counting temperature change. Less energy than a melta, more than a lasgun.

Thank you.

[Connor MacLeod]

Somebody is digging into the plasma gun thread on Spacebattles. LOL

You know you could at least mention that is why you wanted the calc.

[The Reaper]

Somebody is digging into the plasma gun thread on Spacebattles. LOL

You know you could at least mention that is why you wanted the calc.

Actually I just wanted to know how it compared to other 40k weapons. But what is this thread I am hearing of?

[The Reaper]

And that is me on Spacebattles.....sooooo yeah......no one there calced it so i tried it here.

[Connor MacLeod]

Yeah but that isnt an infantry weapon per se. That's more a heavy weapon. As I recall that was a servitor mounted plasma cannon so that's hard to equate with anything the Guard would have (I dont think its common for Guard troops, even heavy weapons infantry, to use plasma cannon.)

Moreover, the calc itself has some issues that will doubtless get argued over. How did cain magically KNOW it was a thousand litres that got vaporized? Did he find out after or is he just guessing? And as mentioned on SB there is the thermal issue - where did all that superheated steam go? (I think the chilling mist might have been liquid thrown off in the vaporization, but there's issues there)

Then there's the fact WR also pointed out, in that plasma weapons, like many other 40K weaponry, tend to have variable effects depending on source and author. Some may cauterize, vaporize, reduce to ash, boil, sear, or any other severely thermal effect. Others may have more explosive effects - blowing people apart or just blowing heads or limbs apart. Some may do both. Some will behave liek a glorified flamethrower even (Ben Counter being infamous for this.) And some merely "incinerate" (which sadly is more open ended than I've treated it.. and the calcs must reflect that.)

The only way to reconcile it is that plasma weapons, like lasguns, are highly variable. You can't even rely on "vairable settings" to cover all this, since 40K weapons don't usually have 16 different settings like phasers do. You have to have different configurations, patterns, models, ammo types, and suchnot to allow for variable effects. Some plasma weapons may only badly burn or have explosive effects - not as energetic as outright cremation but they can still be effective (mechanical effects are generally more efficient destructive mechanisms. Besides you want your enemy to bleed out.) On top of that, the less energy you use to kill the enemy, the more shots you have and the slower the gun heats up (and thus is less likely to blow up in your face.) In the case of "vaporize/cremate" weapons (like in honour guard or Blood Reaver) the plasma weapons probably are firing on a wide dispersion to engulf the target (again more flamethwoer like than anything), which is good for area destruction but will suck at armor penetration. So there are obvious tradeoffs that favor seemingly "lower powered" plasma weapons.

[The Reaper]

Thanks for clarifying, it seems that, like most 40k things it is varying depending on the novel.