...One question though: It was mentioned that when fireing underwater I could experience certain unconfortable situations, especialy at higher pressures. Now what exactly would be happening? Is it a recoil or the pressur eunder water some how rising?
Sound travels 6 times faster underwater. So it's louder for one thing.
On "mythbusters" they did a show on underwater firearm firing and IIRC, a few guns got barrel "bulges" (a dangerous bulge inside the barrel), And a double barrel 12 ga. basically came apart, and would have been unsafe or uncapabable of firing again.
I had limited time online and later thought about your comparison to opening a 100 psi chamber into 100 psi...But it's still different, since the water outside the muzzle would be moved out of the way, not propelled inside the barrel.
Even at deeper depth, less than 50 psi of air/gas inside the barrel would keep water out. Or a revolver type design with each barrel sealed to keep water out should yield a higher velocity than propeling the projectile And the water in the barrel.
@ JSR, that bullet design is exactly the one I was thinking of.
Only longer and with internal fin or rifling even, and sealed off from external water until it exits the muzzle.
I'm stuck on Burst-discs lately, but what about a long projectile like a rocket shape, mounted to a rod with a Burst -disc in the nose section.
That would keep water out and seems good... 1 minute left on-line now
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