On the range for USPSA yesterday. One of the other shooters finished a stage. The R.O. gave the instruction to unload and show clear. The shooter removed the magazine and pulled the slide to the rear. As the round came back it struck something and detonated in the open chamber. No mistakes, just the chance meeting of the primer with enough force to set it off.
The case exploded, sending brass fragments in all directions. One piece embedded itself in the forefinger of his right hand, others cut his left hand. He maintained control of the pistol until the R.O. took it for him.
Immediate first aid was to remove the brass from his finger and control the bleeding. He left the match to get the injury assessed and it took eight stitches to close the wound.
I had only heard of this happening, never been there to see it before.
Assume nothing. Wear your eye protection. Demand that everyone on the range wear theirs. Given enough time, anything that can happen, will.