This high-speed video of an AK-47 firing underwater is pretty impressive:
I liked the explanation near the end.
Naturally, when he pointed out that the bullet only went five or six feet — let’s call it one fathom — I thought of the APS Underwater Assault Rifle, designed to solve that problem — and then he closed by mentioning that his next video would feature Russian frog-man guns!
(Hat tip à mon père.)
You may also like the Mythbusters Bullets Fired Under Water Myth video.
And speaking of the APS, it will be featured in the next Call of Duty game, as seen in this screen-shot!