Is clubbing someone with a gun deadly force?

I got to wondering how the law and LE would view striking someone with the butt of a pistol or long gun. Granted, a gun is a deadly weapon, and you would be using that weapon to assault someone, but in this case, it it used and is no more deadly than a broomstick or pipe wrench. Does it make any difference that it is also a fire arm? Any difference if it's loaded or not?