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We know that for 5.56 M16 ammo power output is around 1,679 J - 1,767 J .
And for 7.62 AK47 is around 2,073.6 J - 2,460 J .
.475 A&M Magnum is around 10,900 J - 12,248 J.

How much in Jules would be power output of standard Imperial Lasgun for:

1. Low setting
2. Medium setting
3. High setting

When determining this, keep in mind that even on low settings, the lasgun effectively causes a tiny plasma explosion where it hits as it superheats the air and material around the "impact" location (thus why it seems to cause impact in the first place). It then flash-boils the blood around the impact wound, causing wounds probably roughly equivalent to hydrostatic shock.

On normal settings, it's capable of removing limbs and heads from bodies. On highest settings, it presents a problem for even advanced body armor, but has few shots, something like ~25 per charge pack.

Melissia wrote:On normal settings, it's capable of removing limbs and heads from bodies.

I know in Dark heresy a lasgun basically causes you to catch fire, have an epileptic fit and then die. But I haven't read any other source where lasguns blow up and removes heads and limbs.

Even in Guants Ghosts, where their allies are using High settings, the las shots are overkill and basically punching straight through the cultists. But they aren't decapitating them or blowing them up.

I think this will be pretty difficult to put a realistic number on considering the smallest ‘weaponised’ laser is the size of your average Smeg fridge/freezer and is fitted in a stripped out F16....even that is only supposed to be used for missile defence and needs to pointed and held for a number of seconds rather than sending a packet/bolt of energy….

Emperors Faithful wrote:

Melissia wrote:On normal settings, it's capable of removing limbs and heads from bodies.

I know in Dark heresy a lasgun basically causes you to catch fire, have an epileptic fit and then die. But I haven't read any other source where lasguns blow up and removes heads and limbs.

Even in Guants Ghosts, where their allies are using High settings, the las shots are overkill and basically punching straight through the cultists. But they aren't decapitating them or blowing them up.

If it can burn a hole through a body, they can decapitate limbs, considering the chest is denser than an arm.

iproxtaco wrote:

Emperors Faithful wrote:

Melissia wrote:On normal settings, it's capable of removing limbs and heads from bodies.

I know in Dark heresy a lasgun basically causes you to catch fire, have an epileptic fit and then die. But I haven't read any other source where lasguns blow up and removes heads and limbs.

Even in Guants Ghosts, where their allies are using High settings, the las shots are overkill and basically punching straight through the cultists. But they aren't decapitating them or blowing them up.

If it can burn a hole through a body, they can decapitate limbs, considering the chest is denser than an arm.

Burning a hole isn't the same as cutting. To cut you have to either move the laser back and forth to cut through like a saw or burn through one section at a time. A particularly powerful laser might cause a localised explosion due to over-heating, but it's unlikely. To take off a limb you need a huge amount of kinetic or thermal energy.

Oh, decapitate means to remove the head.

It is when the method of applying damage is the same. If the heat is strong enough to burn a a hole straight through the torso, a shot of the same strength will burn through an arm, thus making it fall off, but it depends on the area the shot covers. If it hits an arm straight on, when it's parallel to the ground, it will burn through.

I know for a fact that the lasgun can decapitate astartes, so don't think it can't also go through a human limb.

So basically Lasgun on normal setting have energy output of 13.000+ J?

I imagine even on the low setting a Lasgun is stronger than any standard cartridge used by infantry today, probably more similar to a .50 Cal.

Really? Why are than people assuming that modern body armor can protect them from that shot?

Everything that produce mini-plasma explosions on impact is damn scary if you ask me. .475 round could pierce literary every armor we have today, am I right?

I've heard a lasgun can easily go through several feet concrete:

My calculator needed mass, so I put 0.0000001 grams,

Light travels 983571056.43045 feet per second,

V=A x T,

I got 4470217.48 joules.

Completely incorrect, but it gives you the idea of how much energy is carried.

Brother Coa wrote:Really? Why are than people assuming that modern body armor can protect them from that shot?

Because people think that lasguns are flashlights and flak armor is tee-shirts.

Because they stupidly buy into the internet crap.

Melissia wrote:

Brother Coa wrote:Really? Why are than people assuming that modern body armor can protect them from that shot?

Because people think that lasguns are flashlights and flak armor is tee-shirts.

Because they stupidly buy into the internet crap.

You can say that again....

V=A x T

I'm not completely sure that's the best way to calculate the power output of a laser (a photon, though being a minimally massive particle, behaves as a wave). I'd use plank's law: E=h*f. So, a single photon of white-blue light (IG issue, if I remember correctly from Gaunt's Ghosts) transports about 1.655*10^-27 j, while for red light (traitors) we have a 9.457*10^28 j output.
Obviously a las-bolt is a beam of multiple coherent quantums (or quanta?) of focused light, which means things can add up pretty fast. Which does nothing to answer your question.
Now, let's change point of view. Now, let us suppose a normal lasgun battery can be compared to the best modern-days nanotubes and carbon aerogel super-capacitors (with a charge Capacity of up to 6000+ Farads) (I mean, sure las-packs are batteries, but they behave as both batteries and capacitors: they are damaged by fast charging (like batteries), but can be recharged almost indefinetly and provide pulsed energy (releasing great amounts of power in very short times (high power density) like capacitors. Well, lasguns could have internal capacitors, like the flash-light of a photocamera, but they would need recharging times between shots, so bye-bye full-auto or even semy-auto fire)); let's assume they have even some structure similarities to modern days capacitors.
That would mean up to a volume/energy density of 100,000 j/l and, for a battery of about 2x5x10 cm (0,1 l), 10,000 j of energy. Which, for about 40 shots on lowest setting (if I remember correctly form DH), would mean a lousy 250 j per shot. If we consider the mass/energy density we could easily have up to 100,000 J for a 200 g battery, which means 2500+ J per shot on minimum setting. With modern day (even if cutting-edge) tecnology. Add 38k years to that...

It's 60 shots per charge pack, IIRC.


Yep, 60. And that's not the weakest setting, but nominal setting.


Although the primer (IIUP) gives a rate of fire for the lasgun that is slower than most modern assault rifles, it's still more than enough at 220 shots per minute.

I'm fairly sure I read somewhere that they produce 1.21 gigawatts of power.


Automatically Appended Next Post:

Melissia wrote:
Although the primer (IIUP) gives a rate of fire for the lasgun that is slower than most modern assault rifles, it's still more than enough at 220 shots per minute.

Of course it is. Full auto's for idiots.

1,21 gigawatts? Sure, don't worry, your head didn't explode. It just turned out in 1k or somewhere (-when?) like that.

Come on, you just have to go and take it back...
Oh, wait. In 40k that makes perfect sense...

Melissia wrote:I know for a fact that the lasgun can decapitate astartes, so don't think it can't also go through a human limb.

That was after basically shoving it in the astartes face.
I'm sure you can decapitate a human with a modern assualt rifle if you blow their neck to bits enough.



Some people seem to think that Lasguns are super-laser Deathstars and that Flak Armour is near-invincible.
Because they buy into internet crap.

No one thinks that. Nice try though.

Emperors Faithful wrote:I'm sure you can decapitate a human with a modern assualt rifle if you blow their neck to bits enough.

No, it wasn't shoved in the astartes' face.

Sure, if you hit it enough, you'd cut a human's head off with bullets... probably. But a single shot blowing a human's head off would require a rather high caliber weapon. And that's for HUMANS. Astartes aren't human. Their bones are reinforced with non-natural chemicals to make them particularly durable. It's part of their chemical enhancements that go along with the genetic and hormonal enhancements they get. Their ribcage is described as an armor plate in and of itself, for example.

Cut the trolling crap. Noone said that lasguns were uberdeathlasers, we said that lasguns aren't weak.

Seaward wrote:I'm fairly sure I read somewhere that they produce 1.21 gigawatts of power.

+1 for Back to the Future reference.

Melissia wrote:

Emperors Faithful wrote:I'm sure you can decapitate a human with a modern assualt rifle if you blow their neck to bits enough.

No, it wasn't shoved in the astartes' face.

Sure, if you hit it enough, you'd cut a human's head off with bullets... probably. But a single shot blowing a human's head off would require a rather high caliber weapon. And that's for HUMANS. Astartes aren't human. Their bones are reinforced with non-natural chemicals to make them particularly durable. It's part of their chemical enhancements that go along with the genetic and hormonal enhancements they get. Their ribcage is described as an armor plate in and of itself, for example.

It wasn't a single shot, it was a lasgun, on max setting, being poured out on full auto. I'm sure if you emptied a magazine of any assualt rifle into a person's neck then it wouldn't be attached at the end.

Cut the trolling crap. Noone said that lasguns were uberdeathlasers, we said that lasguns aren't weak.

And no one thinks that lasguns are actually flashlights or that flak armour might as well be cardboard. So how about you quit acting like a child and try to have a reasonable discussion without instantly resorting to attacks on the intelligence of peope who don't agree with you.

Well this is gonna end well...

Emperors Faithful wrote:It wasn't a single shot, it was a lasgun, on max setting, being poured out on full auto. I'm sure if you emptied a magazine of any assualt rifle into a person's neck then it wouldn't be attached at the end.

It was one shot that took its head off. Not a full auto burst-- one shot.

Melissia wrote:

Emperors Faithful wrote:It wasn't a single shot, it was a lasgun, on max setting, being poured out on full auto. I'm sure if you emptied a magazine of any assualt rifle into a person's neck then it wouldn't be attached at the end.

It was one shot that took its head off. Not a full auto burst-- one shot.

We are talking about the same Guants Ghosts novel, right?

Emperors Faithful wrote:

Melissia wrote:

Emperors Faithful wrote:It wasn't a single shot, it was a lasgun, on max setting, being poured out on full auto. I'm sure if you emptied a magazine of any assualt rifle into a person's neck then it wouldn't be attached at the end.

It was one shot that took its head off. Not a full auto burst-- one shot.

We are talking about the same Guants Ghosts novel, right?

The first one, First and Only.

Melissia wrote:

Emperors Faithful wrote:

Melissia wrote:

Emperors Faithful wrote:It wasn't a single shot, it was a lasgun, on max setting, being poured out on full auto. I'm sure if you emptied a magazine of any assualt rifle into a person's neck then it wouldn't be attached at the end.

It was one shot that took its head off. Not a full auto burst-- one shot.

We are talking about the same Guants Ghosts novel, right?

The first one, First and Only.

Yes, where the traitor Astartes comes out of the door/elevator/elevatus.

Emperors Faithful wrote:

Melissia wrote:

Emperors Faithful wrote:

Melissia wrote:

Emperors Faithful wrote:It wasn't a single shot, it was a lasgun, on max setting, being poured out on full auto. I'm sure if you emptied a magazine of any assualt rifle into a person's neck then it wouldn't be attached at the end.

It was one shot that took its head off. Not a full auto burst-- one shot.

We are talking about the same Guants Ghosts novel, right?

The first one, First and Only.

Yes, where the traitor Astartes comes out of the door/elevator/elevatus.

Even Abnett can go overboard from time to time. After all, how many times have we seen Guardsmen get hit with lasfire in the novels and pull through?

Not often unless the lasbolt hit armor. That lasbolt hit bare neck when it popped his head off. Frequently those that did survive a direct hit to an unarmored area they were permanently injured.