Back in the early 90's I was a range master conducting a qualifying shoot for the Navy when I was hit in the ribs with a 45 ACP ball riccochet. I was immediately behind the firing line when hit. I do not know how it made it back to me or what all it bounced off of, but it did have dirt and a shiny spot on it. The way some of those guys shot it would not be possible to know where it first struck something to riccochet in the first place. A report was filed, and the berm was rebuilt because of it. I am not aware of it happening to anyone else in my time at that base.
I had a small bruise, about the size of a 50 cent piece, for several days and a story for a lifetime. I still have the bullet somewhere around here. Things happen, be prepared.