>>12160887I don't think you understand what a hydrogen gun is. Look up 'Combustion Light Gas Gun'. That will pretty much answer all of your questions.
> focus light into a beam enough to penetrate a humanThe warhammer meme is accurate, you're talking about going to war with flashlights.
>With rail guns you just need batteries and magnets.Firstly, good batteries are REALLY expensive.
Secondly, you also need a gun assembly that can handle the stresses. For which you need "a stronger material" which, if it's cheap enough to use in the production of guns, will be cheap enough to use in the production of armour.
And you can see the math there. Forces acting on the barrel minus air resistance of the bullet in flight equals energy impacting the armour at the other end. The balance is always in favour of the armour.
Thirdly, you don't need magnets, the gun is the magnet.
