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Logistics also speaks to production, even though a las-gun would be considered a weapon it is certainly a highly advanced optical technology that would require significant tooling, failures in production would make the weapon useless or ineffective. An AK47 can be hammered out by a villiage blacksmith and used for generations with minimal maintenance. I have seen some old AK 47 in use. Ammo can be produced or reloaded locally. Since a bullet kills just as good as a laser it remains more cost effective.

I also disagree on the training aspect. Unless the lasgun utilizes a solid beam it would require significant training to use well. The "speed of light" and exact accuracy becomes a hinderance to an initiate user that still lacks breath and trigger control. If you don't believe me mount a laser on your favorite assault rifle/carbine and try to hold it steady on your target for several moments. You will note the "dot" moving quite a bit as your body tries to maintain your sight picture.

All this aside, lasers are really badass and awesome for sci-fi armies.

- J

 Exergy wrote:
dust in the air, rain, mist, fog, and smoke would be very effective at diffusing the laser beams going in.

And any of the above would also reduce the armor's reflectiveness, rendering it less and less effective.

Ablative armor such as flak is far more effective and reliable than reflective armor, with none of reflective armor's drawbacks.

 Melissia wrote:

 Exergy wrote:
dust in the air, rain, mist, fog, and smoke would be very effective at diffusing the laser beams going in.

And any of the above would also reduce the armor's reflectiveness, rendering it less and less effective.

Ablative armor such as flak is far more effective and reliable than reflective armor, with none of reflective armor's drawbacks.

Depends on what kind of "Flak armour" we mean.

Feral worlds versions of it could be just animal hide, the steel legion use metal plating, normal IG look like they use some kind of kevlar, and the DKOK just have dress uniforms and greatcoats.

 Selym wrote:
Depends on what kind of "Flak armour" we mean.

No. Flak Armor is a specific kind of armor that uses layers of ablative and impact absorbent materials.

Armor such as feral worlders' furs and the like aren't properly flak armor. Valhallan greatcoats are, because the coats are made out of the various materials I mentioned earlier. This, and any differences between the protective power of various styles of flak armor, isn't represented in tabletop because it's a d6 system and is incredibly imprecise.

 Selym wrote:

 Melissia wrote:

 Exergy wrote:
dust in the air, rain, mist, fog, and smoke would be very effective at diffusing the laser beams going in.

And any of the above would also reduce the armor's reflectiveness, rendering it less and less effective.

Ablative armor such as flak is far more effective and reliable than reflective armor, with none of reflective armor's drawbacks.

Depends on what kind of "Flak armour" we mean.

Feral worlds versions of it could be just animal hide, the steel legion use metal plating, normal IG look like they use some kind of kevlar, and the DKOK just have dress uniforms and greatcoats.

Well, if you believe some on here, IG Flak Armor is completely bullet proof, at least to modern ammo. I doubt a lot of animal hide is resistant to most modern bullets.

Regardless, I don't think lasgun is necessarily 'best', it is perhaps the 'most sci-fi' which is why IG have it (ERB first used 'ray guns' in his John Carter books with radium powered weapons. This spawned other 'ray guns' and this has become almost synonymous with Science Fiction). It's also a bit toned down from an 'atomic death ray gun' that was often prevalent.

I'd say, if you want your IG armed with 'ray guns' arm them with 'ray guns'. If you want futuristic assault rifles, go for futuristic assault rifles.

Actually the general consensus is that it's equivalent or slightly better than modern body armor in raw protection (and far better in terms of protection against energy weapons, because we don't use those in modern combat), but it has the advantage of being several times lighter and cheaper to produce.

I doubt a lot of animal hide is resistant to most modern bullets.

We have not yet traveled to other planets with indigenous life-forms to make that judgement.

 Lynata wrote:

Flinty wrote:So there is scope for autoguns to be used on the front lines by standard Guard regiments, but these examples are the minority because its a pain in the bum to supply them. If tehre is a particular need for the particular benefits of the autogun, they will be deployed, otherwise its a bit of a wash and you may as well take the easier option.

Well, the lasgun is noted for being the ONE standard that the Guard manages to enforce for everyone .. or at least tries to, as there are examples of regiments that had to make do with a smaller number of them, or didn't get any at all due to supply issues (leading to a regiment deploying with spears and bows - yay IG). This, however, would be an accident or mistake, rather than intention.

Several of the Abnett novels have teams of various sizes assigned slug throwers for specific missions. There have been single shot marksman rifles and drum mag equipped autoguns. Also its been stated before that PDF regiments are often deployed with autoguns. Its feasible that they could get elevated into Guard status and the aforesaid poor supply situation means they have to do with their autoguns until they can get the right guns. I'm not saying its common, just that its feasible.


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 flamingkillamajig wrote:

To be fair if we're going for this sort of thing what about boltguns working in space? I suppose they could have an oxygen tank to help fire the boltgun but still it's a little odd considering space marines are SPACE marines.

Modern bullets work in space and underwater. The oxygen required to detonate the propellant is bound chemically into the propellant. Detonation happens too quickly for the oxygen to come from the air anyway. Its just a really bad idea to fire a gun underwater as the resulting pressure wave will liquefy your organs...

Bolt rounds would also work in space as the rocket propellant will also have its own bound oxidiser. More of a problem would be the massive range of temperatures that the weapon would need to withstand between the middle of nowhere or in the shade leading to ambient temperatures of about 0K to being in full sunlight leading to massive heating, not to say the thermal change from when the marine goes from in the shade to direct sunlight.


Automatically Appended Next Post:

 Maniac_nmt wrote:

A lasgun would have issues with particularly wet or rainy environments, due to refraction. Also, the power might recharge, but it isn't truly a laser without an excited gas, which would run out. So, if they are actually laser weapons, you'd have two ammo sources, the gas that you excite to fire the laser, and the power cell to do it with.

Solid state lasers exist, and its generally implied this is the kind used in Las weapons.

 Melissia wrote:

 Exergy wrote:
dust in the air, rain, mist, fog, and smoke would be very effective at diffusing the laser beams going in.

And any of the above would also reduce the armor's reflectiveness, rendering it less and less effective.

Ablative armor such as flak is far more effective and reliable than reflective armor, with none of reflective armor's drawbacks.

dust in the air doesnt make a mirror any less reflective. Less light gets to the mirror but what does get there gets bounced back just the same.


Automatically Appended Next Post:

 necrondog99 wrote:
Logistics also speaks to production, even though a las-gun would be considered a weapon it is certainly a highly advanced optical technology that would require significant tooling, failures in production would make the weapon useless or ineffective. An AK47 can be hammered out by a villiage blacksmith and used for generations with minimal maintenance. I have seen some old AK 47 in use. Ammo can be produced or reloaded locally. Since a bullet kills just as good as a laser it remains more cost effective.

Even assuming you could make a power pack that could contain that much energy and recharge itself just by being near heat(with no cold reservoir!) it would be a lot more effective and easier to use magnetic acceleration to push a kinetic projectile rather than convert the power into light and then try and hurt your enemy with heat. Heat is just so ineffective against metal and water, due to the amount required to raise it's tempurature.

Not this discussion again *sigh*
Exergy is pretty much spot on about everything so far. I have handles "real" lasers as well and know my physics.

Real world physics simply cast a very poor verdict on the lasgun so if you are a fan of that then do excuse everything with absurd scifi-fantasy-grimdark-magic.

The only logical answer to why the Imperium uses las weapons in such mass numbers is logistics and apparent ease of production and standarisation, that´s it.
Magical non-real fluff aside, lasers are far easier to protect one self from, do far less damage and are far more environment sensitive then normal kinetic weaponry...but you dont have to drag around heavy ammunition and a logistic train of ammo resupply behind you wherever you go due to the fabulous magical lasgun charge pack that all by itself would be such an incredible scientific achievement that it would rival titans, space ships and anti gravity, lol.

 Pyriel- wrote:
Not this discussion again *sigh*
Exergy is pretty much spot on about everything so far. I have handles "real" lasers as well and know my physics.

Real world physics simply cast a very poor verdict on the lasgun so if you are a fan of that then do excuse everything with absurd scifi-fantasy-grimdark-magic.

The only logical answer to why the Imperium uses las weapons in such mass numbers is logistics and apparent ease of production and standarisation, that´s it.
Magical non-real fluff aside, lasers are far easier to protect one self from, do far less damage and are far more environment sensitive then normal kinetic weaponry...but you dont have to drag around heavy ammunition and a logistic train of ammo resupply behind you wherever you go due to the fabulous magical lasgun charge pack that all by itself would be such an incredible scientific achievement that it would rival titans, space ships and anti gravity, lol.

Thanks.

However bad the real world physics are, I am happy to throw it to the wind in the name of cool. Lasers sound awesome. But having fluff discussions about it are really stretching the limit. It's like comparing psykic powers to projectile weapons. One we know about and can quantify the other is complete suspension of belief.

Yep.
Besides we are forgetting the whole ridicule of visible las "bolts". High energy EM radiation would actually be going far far beyond the UV range and be invisible to us.

Ship artillery in the form of EM pulses would probably be in the x-ray band but I shudder to think of the power sources needed to achieve that
Hell, half the crew would die of from radiation poisoning every time they fired one of unless half the ships mass came from freaking lead and that in itself leads us to another and even bigger technical problem...effective heat dispersion in vacuum. Talk about magical grim dark heat sinks.

Well the ships are many kilometers in length. Plenty of space for even non-magical heat sinks if you give them submarine levels of crampness.

Not to mention superspace technology, better methods of sinking heat.

Really all you need is a way to efficiently transfer the heat into radiative energy which can be dumped into space. Most novels featuring space battles show ships track each other by their heat signature, and they'd definitely have a big one. There could be an as yet unknown element which reacts to temperature by giving off some form of radiant energy. That would be one way of dumping heat.


As for actual power sources, the Imperium does have access to an alternate universe which is nothing but energy, and ships are powered by Warp Reactors. It could be that their ships are partially getting their energy from the Warp itself, with a safe and sanctioned way of course.

 Grey Templar wrote:
Well the ships are many kilometers in length. Plenty of space for even non-magical heat sinks if you give them submarine levels of crampness.

Not to mention superspace technology, better methods of sinking heat.

Really all you need is a way to efficiently transfer the heat into radiative energy which can be dumped into space. Most novels featuring space battles show ships track each other by their heat signature, and they'd definitely have a big one. There could be an as yet unknown element which reacts to temperature by giving off some form of radiant energy. That would be one way of dumping heat.


As for actual power sources, the Imperium does have access to an alternate universe which is nothing but energy, and ships are powered by Warp Reactors. It could be that their ships are partially getting their energy from the Warp itself, with a safe and sanctioned way of course.

It could also be that lasguns have a small fragment of warp energy, that just needs to be unlocked with a continuous charge from a battery.
If that is the case, this would explain why lasguns are capable of even existing, having visible bolts, and only requiring some sun-charged battery power to run.

 Exergy wrote:
dust in the air doesnt make a mirror any less reflective.

Dust on a mirror does make a mirror less reflective.

I even have an exdperiment to prove it to you: take some mud and spread it on your mirror, and tell me if it's still reflecting as well.

Can do the same with dust or mist or any number of things. It's VERY easy to reduce the reflectiveness of a mirror.

Flak armor is way better and more reliable than any sort of reflective armor.

 Melissia wrote:

 Exergy wrote:
dust in the air doesnt make a mirror any less reflective.

Dust on a mirror does make a mirror less reflective.

I even have an exdperiment to prove it to you: take some mud and spread it on your mirror, and tell me if it's still reflecting as well.

Can do the same with dust or mist or any number of things. It's VERY easy to reduce the reflectiveness of a mirror.

Flak armor is way better and more reliable than any sort of reflective armor.

In the air and on the mirror are completely different things.




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 Grey Templar wrote:
Well the ships are many kilometers in length. Plenty of space for even non-magical heat sinks if you give them submarine levels of crampness.

Not to mention superspace technology, better methods of sinking heat.

Really all you need is a way to efficiently transfer the heat into radiative energy which can be dumped into space. Most novels featuring space battles show ships track each other by their heat signature, and they'd definitely have a big one. There could be an as yet unknown element which reacts to temperature by giving off some form of radiant energy. That would be one way of dumping heat.

In space though, there is no where to dump your heat. Heat only propagates through a medium of matter. In a vaccuum there is not heat transfer. Hot things do radiate energy, they create light. So if you were generating lots of waste heat the only way to get rid of it would be to become a bright light.

 Exergy wrote:

 Melissia wrote:

 Exergy wrote:
dust in the air doesnt make a mirror any less reflective.

Dust on a mirror does make a mirror less reflective.

I even have an exdperiment to prove it to you: take some mud and spread it on your mirror, and tell me if it's still reflecting as well.

Can do the same with dust or mist or any number of things. It's VERY easy to reduce the reflectiveness of a mirror.

Flak armor is way better and more reliable than any sort of reflective armor.

In the air and on the mirror are completely different things.

But dust gets on the mirror from being thrown into the air, or by the mirror passing through particles/droplets on the way up or on the way down. Pedantry is all very good, but there are limits

exergy wrote wrote:Automatically Appended Next Post:

 Grey Templar wrote:
Well the ships are many kilometers in length. Plenty of space for even non-magical heat sinks if you give them submarine levels of crampness.

Not to mention superspace technology, better methods of sinking heat.

Really all you need is a way to efficiently transfer the heat into radiative energy which can be dumped into space. Most novels featuring space battles show ships track each other by their heat signature, and they'd definitely have a big one. There could be an as yet unknown element which reacts to temperature by giving off some form of radiant energy. That would be one way of dumping heat.

In space though, there is no where to dump your heat. Heat only propagates through a medium of matter. In a vaccuum there is not heat transfer. Hot things do radiate energy, they create light. So if you were generating lots of waste heat the only way to get rid of it would be to become a bright light.

 Flinty wrote:

 Exergy wrote:

 Melissia wrote:

 Exergy wrote:
dust in the air doesnt make a mirror any less reflective.

Dust on a mirror does make a mirror less reflective.

I even have an exdperiment to prove it to you: take some mud and spread it on your mirror, and tell me if it's still reflecting as well.

Can do the same with dust or mist or any number of things. It's VERY easy to reduce the reflectiveness of a mirror.

Flak armor is way better and more reliable than any sort of reflective armor.

In the air and on the mirror are completely different things.

But dust gets on the mirror from being thrown into the air, or by the mirror passing through particles/droplets on the way up or on the way down. Pedantry is all very good, but there are limits

Sure some dust will settle on the surface. But in battlefield range, you are talking about going through 100-300 meters of dust/mist/smoke filled air, reducing the beam strength and then finally getting to the armor. You might lose 30-70% of the strength just going through some haze. A real battlefield full of smoke and kicked up dust and debris might reduce the strength 95% or more.

Dust/condensation on the armor might reduce its reflectiveness from 99% to 95% unless it is truely covered in mud. If it is still shiny in the least it is going to be over 90% reflective.
Are you suggesting the IG must first fire off mud cannons to make sure their lasguns can actually damage the enemy?

Or more likely, from 99% to close to 0%.

Whereas flak armor has no such restriction. It is effective regardless of the conditions on the battlefield.

I'm not arguing for a lasgun's efficacy here, but that reflective armor is not as good as you claim it to be; ablative armor is provably better in all but the most pristine circumstances.

Or to be more blunt, reflective armor is the Dragonskin of armor against directed energy weapons. It's only good in ideal laboratory conditions, not actually on the battlefield.

 Melissia wrote:
Or more likely, from 99% to close to 0%.

Whereas flak armor has no such restriction. It is effective regardless of the conditions on the battlefield.

I'm not arguing for a lasgun's efficacy here, but that reflective armor is not as good as you claim it to be; ablative armor is provably better in all but the most pristine circumstances.

Or to be more blunt, reflective armor is the Dragonskin of armor against directed energy weapons. It's only good in ideal laboratory conditions, not actually on the battlefield.

mylar weighs practically nothing. You could put it on the outside of anything making yourself virtually immune to laser weaponry. You would still have the flak armor, cermite armor or whatever else you normally have behind it. It isnt an either or type of thing.

The trade of is on visibility. obviously putting reflective film over your armor will make it easier to see you than sophisticated camoflague. Look at the armies in 40k, how many of them use camo? Not many.

 Exergy wrote:

Sure some dust will settle on the surface. But in battlefield range, you are talking about going through 100-300 meters of dust/mist/smoke filled air, reducing the beam strength and then finally getting to the armor. You might lose 30-70% of the strength just going through some haze. A real battlefield full of smoke and kicked up dust and debris might reduce the strength 95% or more.

Dust/condensation on the armor might reduce its reflectiveness from 99% to 95% unless it is truely covered in mud. If it is still shiny in the least it is going to be over 90% reflective.
Are you suggesting the IG must first fire off mud cannons to make sure their lasguns can actually damage the enemy?

The following is based on pictures and footage I've seen of real battlefields (ok, maybe except for the lunar bit...). I haven't made a particular study:
- Temperate battlefield - mud is a natural consequence of the kind of large explosions that put particles up in the air and of soldiers taking cover. If you're on rocks rather than earth then you've got the scratching effect of gravel rather than mud, but that would still affect the reflectivity of the surface
- Desert battlefield - sand and dust can become electrically charged and tends to stick to surfaces, replicating the effect of mud on surfaces. Sand will also scratch the surface affecting its reflectivity.
- Ice battlefield. this is probably the worst case for lasers as the stuff that might stick to the surface of the mirrored armour would be ice and snow, although mud and gravel would still be a problem
- Lunar battlefield - Moon dust is known to be a pain in the bum fro sticking to stuff and acting as an abrasive

From what I've seen of soldiers in real battlefield conditions, they get mucky really quickly



Automatically Appended Next Post:
Also unless a surface is 100% reflective then it would still absorb heat from the laser. If you're relying on a thin film of reflective material its still likely to ablate away before the full energy of the laser pulse has dissipated so you would still get energy leaking throguh to the target.

Oh for gawds sake...

The argument so far:

-Lasgun/autoguns technical specifications and related efficiencies

-lasgun = pew pew layzors, therefore it is really ineffective

-lasgun = sci-fi magic, is effective.

-lasgun = heat based damage, sometimes effective

-lasgun = exactly the same as sunlight, reflective armour is lasgun-proof

-dust = lasguns are useless

-dust = reflective armour is useless, lasgun still useful

-dust = both are useless, what was the point?

- [related circular arguments]

-reflective armour is capable of perfectly reflecting 99% of a lasgun's heat damage

-reflective armour is not capable of doing the above.

-this post.

Just so we all know where we are in this... thread.

Yes... but I joined a stupid on line forum so I could discuss stupid stuff on line. Keeps me from boring my wife to death with my BS. Works pretty good too.

/ Las-guns will never work. Look cool in movies tho. By the way the US Army has genuine directed energy weapons. Go "google" the "pain ray." Also check out the airborne defense laser. This stuff just doesn't translate to "man portable." I can actually see a crew served lascannon being useful - lasgun... NAH!

- J

 Pyriel- wrote:
Not this discussion again *sigh*
Exergy is pretty much spot on about everything so far. I have handles "real" lasers as well and know my physics.

Real world physics simply cast a very poor verdict on the lasgun so if you are a fan of that then do excuse everything with absurd scifi-fantasy-grimdark-magic.

The only logical answer to why the Imperium uses las weapons in such mass numbers is logistics and apparent ease of production and standarisation, that´s it.
Magical non-real fluff aside, lasers are far easier to protect one self from, do far less damage and are far more environment sensitive then normal kinetic weaponry...but you dont have to drag around heavy ammunition and a logistic train of ammo resupply behind you wherever you go due to the fabulous magical lasgun charge pack that all by itself would be such an incredible scientific achievement that it would rival titans, space ships and anti gravity, lol.

The Gods of Chaos laugh at your "physics". Laugh at them from their mountains of blood-spattered skulls/naked, sexy body-things/gross, squirmy plaguey things/crystallized dreams and hopes and thoughts.

Especially because we have, fairly recently, created lasers. The setting of 40k has an additional THIRTY-EIGHT THOUSAND YEARS to make them better. Think about that for a moment. Thirty-eight thousand years. That is more than four times the entire length of human civilization from its very beginnings to the modern era. We went from baking mud bricks in the sun and carving cuneiform characters on stone tablets to digital, globe-spanning communications and space exploration in only ten thousand years. Give ourselves four times that span? We're going to have some pretty nifty shiznit.

It's a sci-fi-fantasy game. The minute you try to bring real physics into the discussion is the minute you lose, because you are *required* to suspend your disbelief by the setting. This is not hard sci-fi. The creators are not physicists or engineers or anything of the sort... they are comic book fans, RPG players and fiction authors.

 necrondog99 wrote:
Yes... but I joined a stupid on line forum so I could discuss stupid stuff on line. Keeps me from boring my wife to death with my BS. Works pretty good too.

/ Las-guns will never work. Look cool in movies tho. By the way the US Army has genuine directed energy weapons. Go "google" the "pain ray." Also check out the airborne defense laser. This stuff just doesn't translate to "man portable." I can actually see a crew served lascannon being useful - lasgun... NAH!

Everything miniaturizes but I dont see laser weapons being cheaper or more effective at killing people at close range than kinetic weapons. Their primary advantage is speed to target and ability to track fast moving targets/engage multiple targets quickly. Both of these get much more important over long range, well beyond the range of standard infantry weapons.


Automatically Appended Next Post:
Interesting side note:
Assuming all targets have the same reflectivity, around 30%

Water has a specific heat of 4.18J/gK so it takes over 4 Joules to heat 1 gram of water 1 degree K or C
Flesh is only mostly water and has a specific heat of 3.5 J/gk

Assuming bad things happen at boiling, and flesh starts at 30 degrees C, needing to get to 100 to boil it would take 245 Joules to vaporize one gram of flesh.
Steel has a specific heat of .466 so raising its temperature would be easier. You could however need to get it to a higher tempurature to get it to melt. dT= 1350. It requires 629 Joules to melt a gram of Steel.

But we all know steel is heavier than flesh, in fact it is 8 times more dense.

Assuming one of these Lasguns has the punch to put a whole in a man, all the way through the chest, say 20cm then it could also go through 1cm thick steel. 20cm of flesh isnt that much, most hand guns can do that with ease. Few can go through 1cm of steel plate. Another way, it could go through .2cm of steel plate and have virtually the same stopping power+molten steel would probably leak onto the inside of the armor.



Now one can argue you need not vaporize flesh to hurt someone, merely heating their flesh up would probably cause extreme discomfort but that is what the fluff says. The temperature band in which electronics work is very thin, you would not need to penetrate the armor to get to them, merely warming them would render a electrico-mechanical system useless



I am starting to think lasguns should be more like hot shot lasguns. Able to penetrate armor but not being very high strength.

 Exergy wrote:

 Melissia wrote:
Or more likely, from 99% to close to 0%.

Whereas flak armor has no such restriction. It is effective regardless of the conditions on the battlefield.

I'm not arguing for a lasgun's efficacy here, but that reflective armor is not as good as you claim it to be; ablative armor is provably better in all but the most pristine circumstances.

Or to be more blunt, reflective armor is the Dragonskin of armor against directed energy weapons. It's only good in ideal laboratory conditions, not actually on the battlefield.

mylar weighs practically nothing. You could put it on the outside of anything making yourself virtually immune to laser weaponry. You would still have the flak armor, cermite armor or whatever else you normally have behind it. It isnt an either or type of thing.

The trade of is on visibility. obviously putting reflective film over your armor will make it easier to see you than sophisticated camoflague. Look at the armies in 40k, how many of them use camo? Not many.

Excepting the fact that lasguns in 40K have both a thermal *and* a kinetic force. That mylar covering on your armor doesn't bounce the laser, it just melts as you get whacked with the white-hot baseball bat of force in the chest/shoulder/arm/leg/head/wherever you caught a round. It's not a "beam" of light, more like a bar or a bolt. It's more Star Wars blaster than Star Trek phaser... and does, also, somehow, create recoil, at least according to certain fluff.

 Exergy wrote:
mylar weighs practically nothing.

And it's quite easy to ruin its reflectivity and requires constant work to maintain it, especially in a place like a warzone.

Or to be more blunt, it's not worth it when it provides zero real benefit compared to just having thicker flak armor, which is not only better than reflective armor, it's also good against more than one kind of weapon. Reflective armor is pointless when there are better, cheaper armors out there which have fewer drawbacks.

 Psienesis wrote:

 Exergy wrote:

 Melissia wrote:
Or more likely, from 99% to close to 0%.

Whereas flak armor has no such restriction. It is effective regardless of the conditions on the battlefield.

I'm not arguing for a lasgun's efficacy here, but that reflective armor is not as good as you claim it to be; ablative armor is provably better in all but the most pristine circumstances.

Or to be more blunt, reflective armor is the Dragonskin of armor against directed energy weapons. It's only good in ideal laboratory conditions, not actually on the battlefield.

mylar weighs practically nothing. You could put it on the outside of anything making yourself virtually immune to laser weaponry. You would still have the flak armor, cermite armor or whatever else you normally have behind it. It isnt an either or type of thing.

The trade of is on visibility. obviously putting reflective film over your armor will make it easier to see you than sophisticated camoflague. Look at the armies in 40k, how many of them use camo? Not many.

Excepting the fact that lasguns in 40K have both a thermal *and* a kinetic force. That mylar covering on your armor doesn't bounce the laser, it just melts as you get whacked with the white-hot baseball bat of force in the chest/shoulder/arm/leg/head/wherever you caught a round. It's not a "beam" of light, more like a bar or a bolt. It's more Star Wars blaster than Star Trek phaser... and does, also, somehow, create recoil, at least according to certain fluff.

Light conveys momentum. The sun has a solar wind constantly pushing things away from it. There are intersteller designs being thought of that use stationary lasers to push craft up to relativistic speeds.

It doesnt have much momuntum, but in the scale needed to vaporize a significant amount of flesh, it would probably kick a lot.

 Kasrkin229 wrote:

Stopping Power
In 40k fluff it is suggested that lasguns have little to no recoil , and as per Newtons law stating that for each reaction there is an equal and opposite reaction , the "beam" from a lasgun is never portrayed as having any sort of stopping power in comparison to solid slug projectiles this could be a critical draw back when fighting enemies that in the face of any kinetic projectile would be stopped or at least slowed would simply shrug off las-fire . This is critical in that the basic trooper would get extra seconds needed (hopefully ) from a weapon that had physical "kick" to it rather then something that was a simply beam of light

That is not what stopping power means. By that logic, a lascannon also has no 'stopping power' due to the projectile (energy emissions) having negligible mass. Stopping power refers to the ability of a weapon to cause an injury that will incapacitate a target. Having a large section of flesh exploded from your body (depending on where you look in canon, this could extend to blowing off unprotected limbs in a single shot) is going to incapacitate anything that a bullet would. Orks would not at all be slowed by the weight of a bullet entering their bodies, unless the bullet was so extremely heavy or traveling so extremely fast (without just completely killing or penetrating the target) that it would provide enough force to physically stop an Ork in his tracks. Anything capable of doing this would not be an infantry weapon, and would be hard-pressed to slow a target without immediately popping them like a meat balloon (not that this is a bad thing). By your definition of 'stopping power', a good punch is more effective than being shot with a light pistol.

Armor Penetration -
ah the Famous downfall of the simply lasgun its lack of ability to pierce any armor , even that piece of leather worn by the creepy Slannash cultist ( joke )
regardless in fluff and in many books ( ill agree isn't exactly a consistant source ) Las-guns to posses the ability to slice though standard imperial Body armor its effect is greatly dimished when anyone decides they want to wear something with even a remote heat-dissipation ability this effect is greatly diminished and even in some cases almost entirely lost ( mainly looking at space marine adamantium and similar materials ) while an Autogun firing simple Steel Jacketed ammunition ( i personally have put a 7.62x54mm steel jacketed round though a 1.5 inch steel plate 9/10 times it penetrated ) would be much more capable of dealing with armor that was ballistically rated armor as well as heat rated armor - Mainly due to that when a ceramic plate ( for current body armor i can only assume that a similar standard would apply with futuristic armor and bullet propelants ) the impact from the round will most likely crack or shatter the plate rendering it ineffective , this is mainly solved by having multiple overlapping plates to disperse energy over a large area so the plates do not become over stressed and crack . Alot of my Argument will fall to the " Its science fiction " or " its 40k no reason here !! " However i can only speculate as to the different advantages and disadvantages at this time --- anyway back on track i do believe that the lasguns lack of ability to defeat very simple heat absorbent armor is its ultimate downfall here

Real-world ammunition is not a basis for comparison. No armour in 40k is 1.5 inch steel plate (something which a lasgun would have absolutely no problem penetrating ). Space Marine ceramite and adamantium would stop a lasgun shot, sure, but it equally nullifies autogun shots. Your argument that '"i personally have put a 7.62x54mm steel jacketed round though a 1.5 inch steel plate 9/10 times it penetrated" + 'lasguns suck against Space Marines' = autoguns are better' is inherently flawed. Space Marine armour is not 1.5 steel plate, nor is even the most lowly armour in the game. Also, the way you word your statements about lasguns speak of obvious bias - "when anyone decides they want to wear something with even a remote heat-dissipation ability this effect is diminished and even in some cases almost entirely lost". This is a weapon that can easily sever limbs. This is like me saying that real-world sniper rifles only work when people forget to wear a hat, just because I dislike them (or alternatively really like hats and wish to promote their ballistic-resistant properties).

Damage to Target ( high speculated ) -- So it is commonly accepted that a las-bolt when it strikes causes a mini-explosion as the liquid in the cells surrounding the impact site instantly boil from the head and explode causing a suprisingly large amount of damage - this would be awesome if the wound didn't mostly cauterize upon impact as well as leaving behind very little pain due to the fact that when the nerves are exposed to flash heat such as that , the die and are sealed before they can transmit any signals of pain to the brain . Further more the cauterizing effect also makes it impossible for the victim to bleed out enough to cause shock , where as the shock that does ensue will most likely be from the mental mindset and seeing the injury ,

That is a woefully inaccurate description of how cauterization, pain, and shock works.

this is all fine and dandy when fighting other humans but when engaging a foe that feels no pain or is on a combat "high " ( Orks ect ) the shock won't set in and lacking of bleeding caused by the wound will make it extremely unlikely to render such an opponent incapacitated by a las-shot . This brings up the point where Slugs from an Autogun would be prefered As when the slug hits , the round entering first would have an immediate entry wound afterward the round would ( usually) begin to tumble after the primary expansion in which case Fragments break off from the round , this causes massive internal hemorrhaging and after several rounds could very well incapacitate a larger opponent though blood loss , as the shot itself may not be felt by the victim they will not be able to ignore the fact that their blood is now pouring onto the ground . granted this process will be very different depending on the Size , strength , and endurance of varying opponents but at least its something compared to our auto-cauterizeing friend

Actually, this is so much not even wrong that I'm just going to leave this thread for my own sanity.

Water has a specific heat of 4.18J/gK so it takes over 4 Joules to heat 1 gram of water 1 degree K or C
Flesh is only mostly water and has a specific heat of 3.5 J/gk

Assuming bad things happen at boiling, and flesh starts at 30 degrees C, needing to get to 100 to boil it would take 245 Joules to vaporize one gram of flesh.
Steel has a specific heat of .466 so raising its temperature would be easier. You could however need to get it to a higher tempurature to get it to melt. dT= 1350. It requires 629 Joules to melt a gram of Steel.

Lasguns are measured in an energy unit referred to as a "megathule" (18 of them, if I remember my Uplifting Primer). What, exactly, a megathule is, though, is not provided. It is commonly believed, in threads like these, to mean a "mega-joule", but there's nothing to support that other than the fact that they sound the same.