Bullet in water ?

Question

If i gun was fired from 10 metres, 45 degree downward angle, into water.

a) Approximately how deep could the bullet travel before stopping ?,
b) would the bullet fragment on impact with the water ?
c) could the bullet injure somebody 10 metres under the water ?

My initial thoughts are <10 metres, yes, no
But I would like some more info.

Answer 1

The penetration depth depends to a great degree on if and for how long the projectile remains intact.

Suffice it to say, high velocity (~3000fps) rifle bullets, even with full copper jackets, disentegrate very quickly upon impact with water. I've seen this effect in person.

I doubt you could achieve any significant penetration at 1 meter, much less 10.

I suspect that variations in dynamic pressures caused by fluid flow and cavitation across the bullet's surface literally rip the projectile apart. It's quite probable that a high-velocity rifle bullet could penetrate farther through many solid materials than through water.

Answer 2

Depends on the type of firearm. The distance a bullet will travel underwater depends on it's velocity and mass. Are you talking about a 22 cal. pistol or a 30-06 rifle?

Since water is so much denser than air, the bullet will slow down much, much faster in water. Odds are that 10 meters of water would make the bullet pretty harmless. That's over 30 feet.

The bullet probably won't fragment on impact with water. A lot of low enforcement agencies use water traps to when they want to collect a bullet fired from a specific gun for ballistics comparasions.

Answer 3

Forensic investigators often have to test fire weapons into a water tank to retrieve undamaged rounds for comparison with crime scene evidence. The link shows such a tank that must be of more than adequate depth for many types of rounds. The distance fired from above the water should have little effect even though the tank is used at close range for safety. The bullets should not fragment.

Answer 4

Mythbusters did this experimet. With one of the first rifles invented with a bullet speed of 200 meters/second the penetration in water was under 2 meters. With a state of the art modern rifle with a bullet speed of 900 meters/second the bullet exploded on impact with the water surface...so almost 0 penetration. If a person is more than 2 meters underwater he should be fine.

Answer 5

It depends on the size, shape, and velocity of the bullet. Watch Mythbuster's on Discovery channel for a great demonstration.

One big thing they found out is that with high velocity rifles (sniper rifle) the bullet explodes when it hits the water.

On a side note, I can't believe that Jamie was dumb enough to fire a shotgun into plexiglass tank!! Especially in the shop!!!

Answer 6

This was actually tested on the Discovery Channel program "Mythbusters." They discovered that it depends on how powerful the gun is; high powered sniper rifle shots pretty much disintegrated into shrapnel on impact and didn't penetrate very far at all. Lower powered guns like pistols held it together and penetrated further, but lost all their momentum in about eight feet. So at 10 meters, you're safe from pretty much any handheld weapon (though I suppose if they were aiming a grenade launcher at you, you might have some problems)

Answer 7

Surely it depends on the type of guna nd the type of ammunition.

I'd imagine a standard type hand gun would travel a fair way, and no I don't think it would fragment and yes I think it would injure the person.

Answer 8

a to the bottom of the resevoir (bullets don't float)
b no
c baring explosive shells no way , there was a mythbusters episode about this, your actually safe about 3 meters underwater from even a heavy machine gun

Answer 9

Unless it is a high powered rifle most bullets are relatively harmless after 6-10 feet.

How far would it go? It would sink until it the bottom. ;)

Answer 10

Depends on the gun and bullet. Too many unknown factors.