Mythbuster Question

Eaglewood

Sr Member
Does a gun fire underwater?? and if so , how long can you keep it underwater before it wont function?

I know the bullets dont go too far cause I saw that episode, but they were firing from the air INTO the water--

Just curious is all
 
They did an episode where they fired guns while the guns were underwater too, wont tell you the results in case you want to see for yourself.
 
Found this online.

confirmed
Bullets Fired Into Water

Original Bulletproof Water episode

This time around, they want to test if it was possible to fire ordinary guns underwater. There were to questions in particular they wanted to answer:

* Will an regular gun fire underwater?
* At what distance is would a bullet (from a regular gun) fired underwater be lethal?

Test setup:

* Water trough that the bullets were fired through
* Movable ballistics gel target to test lethality

Test weapons:

* Colt King Cobra, .357 magnum full metal jacket
* Sig Sauer P239, 9mm
* M1 Garand/.30-06
* 12-gauge shotgun

There are Special Forces guns that can fire underwater (Glock 17, Russian SPP-1 underwater pistol), but they wanted to test whether 'regular' weapons could do the trick.

Tory made sure that there was no air in the barrel because, if there was, the barrel could explode.

The first up was the 9mm. Without a ballistics gel target, the bullet went 18 ft. This answered the first question: yes, you can fire a regular gun underwater (confirmed). The 9mm bullet was intact, but the casing wasn't ejected from the gun. Instead, it was stuck in the slide, so you would only get one shot underwater.

Now they had verified that you can fire a gun underwater, they moved onto testing lethality. In the original episode, they found that a 9mm gun fired into water was lethal at 8ft. No so for a bullet fired underwater: the 9mm bullet didn't even come close to penetrating the target at 10ft. They next moved the target to 2ft, at which point they couldn't find the bullet. Same with the .357 magnum: they lost the bullet when fired at 2ft from the target.

Back at the shop they dissected the ballistics gel block and found the 9mm at 4" deep and the .357 magnum at 5.5", i.e. both would be lethal at 2ft.

The other guns didn't fare as well. The 12-gauge shotgun cracked on firing with heavy damage to the barrel and stock. The impressive M1 Garand also fared poorly. The M1 has an exit velocity of 2700 ft/s, 3 times the energy of the other guns they were testing, but in the original Bulletproof Water episode, they had already seen it fail to shoot into water -- bullet shattered on impact. The firing underwater was equally unimpressive: the bullet was intact, but it only went 6 ft, less distance that the 9mm.

You can fire a bullet from a rifle or handgun underwater: confirmed (you can't use a shotgun underwater). However, it is more lethal to fire into water than it is to fire underwater.
 
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Primer and powder in bullets have enough oxydizer to fire both underwater and in a vacuum.

But it can create dangerous, and possibly fatal pressure spikes in the barrel.

So it's not a very good idea overall ...
 
Defstar--- thanks so much --pretty much confirms what I thought --Another one bites the dust LOL

Yeah they'll fire but pretty much useless unless the targets 2ft or so away from you and the shotgun was a real mess you wouldn't be wanting to hold that.

All in all you'd be better off pistol whipping someone underwater than shooting at them with a regular gun :lol
 
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Interesting to me, that they made sure there was no air in the barrel. It seems to me that it would be far safer to have a very compresible medium, like air, in the barrel rather than an incompressible medium, like water.
I bet the lethal distance would have been farther with out the pistoning of water in the barrel and it was, I beleive, the big reason the larger bore weapons suffered failure or very poor performance. With the shotgun they were trying to accelerate .3 pounds of water to 1200fps in addition to the shot(an ounce?)
 
Here's one I've been wondering about...We all know that if you chomp a wintergreen lifesaver it makes sparks. Are those sparks strong enough to ignite say Gasoline fumes. IE some mook at a gas station chomps his lifesaver and Blooey.
 
I have heard that standard Glocks will function underwater, but that they ideally require the addition of a special kit - different recoil spring, guide rod end cap and a couple other little bits - use those and the performance is supposedly fair to reasonable.

I also heard Sig Sauer made one or two designed for Special Forces that will work OK-ish underwater...
 
We DO all know this???? Hmmm you know what they say about assuming:wacko

LOL

First time in my entire life Ive heard that one :confused
I learned about Wintogreen and Peppermint life savers sparking when you bite one 37 years ago. The trick is to bite with your mouth open, in a dark room, in front of a mirror.
 
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