Do guns go off?

[Xeranox]

In movies, people are often pointing guns at each other. My question is this: If person A fires the gun at person B, will the gun of person B automatically go off when he'* ***?

[JackDanielsU]

Like the way it cancelled out the word hit and the 's in your question

I guess the answer is yes..purely reflex action. Unless you shoot the guy in the shoulder area, and by all accounts that hits the muscle that makes you drop the gun (Saw that in a film so its got to be true)