Do guns truly fire underwater? (1 Viewer)

[Stan]

Maybe a completely inappropriate subject so not sure if thread will be shut down.
Just something I've always been cuirous about, Happened in last night's repeat of "Castle" when Beckett and Castle were in a car, pushed into the Hudson river and proceeded to sink. Eventually escaped, obviously since they're the main characters, by finding Beckett's gun and shooting out the windows, even though gun had been underwater and the car was nearly 100% filled with water.
Will a gun fire underwater? Or is this just a movie/TV plot device used for convenience?
Don't you need gaseous oxygen to make a spark and fire a bullet? Underwater that's obviously not available.

 

[Dennis Nicholls]

You have to remember that a sealed cartridge has air in it - enough to fire the charge. The real danger is that the barrel is full of water. This acts like a "plugged barrel" in that the water can't get out of the way fast enough. I would guess (I don't fully know) that the gun would blow up in your hand.

 

[Greg_S_H]

Nah, you can go on YT and see plenty of people firing Glocks in their pools. It's not very effective and I wouldn't do it, but it can be done. It might have been better for Castle to have used it like a hammer, but maybe if he pressed it to the glass.

 

[schan1269]

The most well known gun that "won't fire when wet" is the AK47. But, from what I've been told, there are workarounds.
The main disadvantage to firing underwater is the lack of accuracy followed immediately by the "lack of deadly force"...even if you did manage to hit your target.
Same rule applies to firing a gun into the water...accuracy goes to hell...and if you did manage to hit the target, more than 10 feet of water travel renders the bullet "non-lethal"...
However...underwater guns intended to fire darts (MK 1) work fairly well under water, but above the water...you better be within 40 feet of what you are aiming at...otherwise you might as well throw it hard.

 

[Ken Chan]

The bigger problem might be firing inside the car filled with water, when neither of them had ear and eye protection.