If you look very closely, you can see that this zombie is fake:

the .50cal is real tho.. lmao

And a very good demonstration of what it can do, IMHO!

Here's a more humorous example:

(actually it's a .60 cal but a hand cannon is a hand cannon.. lol)

Wow, now I know why they call it a hand CANNON.

Maybe so, but this is the biggest bad boy around and the sheeet: even if you can't handle firing it you could probably just throw the rounds at someone and knock them out, or club them into oblivion with gun itself.