i don't know how these guys do it.

I think this was already asked elsewhere, but anyways, the barrel itself is recoils into the hull of the tank, the loader sits to the side of the breech. AQuite a few people have gotten pretty injured by being in the way, thus in training, they drill into your skull "don't stand in fron of the breech". Also, if you see an Abrams fire while stopeed, the recoil sends the whole vehicle onto one tread, kinda awesome looking actually.

Asked and answered. (Thank you, Nero. )