LOL! Ian. I was priming brass about 35+ years ago and my wife wanted to help.
She was holding the Lee priming tool at max arms length and cringing every time
she seated a primer. I said, "They really aren't that big a deal, here let me show you"
I grabbed my Colt Gold Cup and put a primed case in the chamber and pointed it
across the basement away from us and pulled the trigger. YIKES! That was LOUD.
She looked at me doubtfully ("that was dumb", look) and said, "Well, it makes my ears ring." I admitted
that it was a lot louder than I expected, but said that pointing the case mouth it away from herself (and she
was wearing shooting glasses, at my original insistence) was, obviously, a great idea, but that
it was pretty difficult set one off unless you hit it with a firing pin. I have yet to EVER set off
a primer while seating it, including a couple which got sideways and crunched into place before
I knew what had happened.
Primers are reasonable safe, but eye protection is mandatory.
Bill