If you have to fire your rifle underwater, it is safe to say you are probably having a bad day. I mean who knew zombies could swim? Richard Ryan Rated RR FullMag does some cool underwater tests with a few different types of AR and AK rounds. Check it out:
I guess it isn't terribly surprising that the gun damn near blew up. Folks, it is a bad idea to try your favorite rifle out in your backyard pool.