I've been reloading for 55+ years, every once in awhile you do something that makes you think "idiot, why did you do that?"
Yesterday I was annealing some 6BR brass with my AMP. I have accidentally annealed cases with live primers in the past without an issue. I make an effort not to that, but it has happened. I cringe every time one slips thru.
Well so this time, when I dropped the case in the tray with previously annealed cases it must have laid against a hot neck, BOOM!
Felt a sting in my chest, ouch. Had to use twisters to remove the blown primer.
So I get to wear the idiot cap for awhile, at least til it heals up.