We were at an indoor pistol range in Maryland. There were two middle-aged men in the lane next to us. They had a collection of older .25 autos, and were fiddling with them. We started to shoot, and took a break after about 15 minutes to change targets. While doing so, I heard a crack, and a really strange noise just above my head. As I glanced up, I noticed pieces of the ceiling tile drifting down. The man had discharged the weapon while aimed up, and back! I guess he was flinching in response to it's immense recoil?
I headed out, got the Range Master, and he at first talked to the pair, and then ordered them, after he had insured that their weapons were indeed onloaded, off the range. He told me that the man advised him that he always started, finger on the trigger, from a position directly above his head, arm outstretched, and then brought it down and onto target to "simulate real life". My guess was that he spent a lot of time in the "put your hands up" position in real life.