We have an elderly cat - tonight I found large sticky patch on his head, cleaned it off, it was blood. There was a deep puncture wound, just one. Looked very much like a pellet or bullet puncture to me (no tearing as you'd expect from a claw or if he'd got caught on something). I strongly suspect he'd been shot with a pellet gun and the pellet had not penetrated his skull.
Cat was very good about me cleaning off the wound - but afterwards made it clear he felt he'd earned multiple cat treats.