OUCH!! I've seen some nasty accidents caused by using a framing nail gun improperly but nothing quite like that.
The funniest was when I was working as a framer, building houses. We were nailing down the plywood decking on the second floor of the house. Now using a nail gun certainly speeds up the process as apposed to hand nailing. But you still have to take some time to insure that the nail hits the joist and all.
Well, one of the guys was doing the nailing as I was cutting and placing the odd shaped pieces. He was going very fast and talking to one of the other guys. all of a sudden I hear this scream and the nail gun gets dropped. He'd put two 16D, long nails, through his foot, through the plywood. Blood everywhere, of course. Couldn't move or remove his foot. Couldn't just pull it up so we had to cut a piece around his foot so we could take him to the Hospital. I remember the foreman tell him,' don't come back without that piece, we need it to finish the deck'. No concern for the guy just get the job done. It was pretty funny when we got to the Hospital. People in the ER were taking pictures supposedly for their 'records'. Still, kinda' funny.
Jar