will a machine gun work under water?

Question

i have just watched leathal weopon 4 and riggs shots the triad guy with some sort of machine gun when they are fighting under the water i was wondering if it could be done realy

Answer 1

Yes, the bullet will fire. (there is enough air in the casing to support the "explosion" to fire it), but it will not be effective for any distance due to the water in the barrel. It will most likely ruin the barrel and damage the rest of the firing mechanism in the process.

Answer 2

A lot of reasons why a machine gun would not work
Starting with the bullet
no problems ther its waterproof and has the required oxygen in the propellent.
when the weapon is cocked the breach-block is pulled back against the power of a spring. When the trigger is pulled, the block is pushed by the spring collects a bullet from the magazine and pushes it into the breach till the fixed fireing pin hits the detonating cap on the bullet. The explosive goes off and the bullet shoots forward at the speed of sound or higher.
So far your underwater machine gun may have worked.
but this is where the problems start.
water does not like being moved arround at the speed of sound so as the bullet travels up the barrel it very quickly compacts the water in the tube to such an exted that it would probably blow the barrel apart.
OK Lets assume the barrel suvived
Machine guns are re-cocked (made ready for the next shot) by the pressure of gas behind the bullet when the bullet passes a certain point in the barrel it goes past a small hole. The gas now has a way to escape the confines of the barrel up the hole. it is fed baclk to a piston attached to the breach-block and this pushes it into the ready posistion, but like the barrel this is full of water so would not work correctly. Hence the gun cannot recock itself and the second bullet cannot be fired

Hope this helped answer your question

Answer 3

Any bullet will fire under water, as both components of the chemical fuel reaction are contained within the explosive mix in the cartridge. It does not use oxygen from the air.

However, a machine gun does not have any batteries or anything to power it. It uses the "kickback" action of the first bullet firing to eject the spent cartridge and to load and fire the next bullet. Therefore some of the energy of the explosion is directed at carrying out this function.

Machine gun manufacturers want to use the least energy from the bullet firing explosion to do this work, so that maximum energy is directed at sending the bullet on it's way.

Hence above water a machine gun works fine, but below water the mechanism for ejecting spent cartridges and loading and firing the next bullet will become filled with water. This water acts as a drag on the "eject - reload - fire" mechanism (just like when you try and run in waist-deep water), and not enough of the energy from the explosion of the first bullet will be directed at "eject - reload -fire" for the next bullet to overcome the water drag on the mechanism.

Hence a machine gun will only fire the first bullet.

There is no reason you can't design a machine gun where more of this energy is directed towards "eject - reload - fire", enough to overcome the water drag, but then above water it's performance will be less than the equivalent existing machine guns when fired above water.

You can't have your cake and eat it, unless you use some other external energy source to carry out this "eject - reload - fire" function.

Answer 4

Mythbusters tested guns under water. I don't know about a machine gun but a pistol will fire.The Russians developed underwater pistols. See link below. It towards the bottom.Muzzle velocity varies according to depth.

Answer 5

Yes. Mythbusters proved that a gun can work under water but you'll have only one shot 'cause the gun usually is destroyed after that.

Answer 6

Yes, it will. But after a few minutes in the water, the ammo would get damp inside and not work. You would have to replace the ammo with dry and start again! That's why we hold weapons over our heads when fording rivers etc.

Answer 7

yes it will fire. no it wont be a good idea. i think the water in the barrel would, or may cause the barrel to backfire.
it'd probably kill ya.


also firecrackers will explode under water, but the paper fused ones may go out. the m series crackers will not extinguish. the fuse is water resistant or something.

Answer 8

No, it will not. The simple reason is that the density of the water would slow the projectile down to much. In the television series "Myth Busters", they did a very interesting program about such as this. You might want to see if you can get any data from them.

Answer 9

On the face of it I can’t see why not.... The depth of water would certainly affect muzzle velocity but I don't see why, on a modern gun, the basic function of firing would be prevented?

Answer 10

Yes any gun will fire under water and have infinite ammunition unless the actor has to change a magazine for effect you also never have to clean a weapon and it will never jam....
Ain't Hollywood great....