primers are dangerous. thats exactly why i dont use a hand primer. i threw mine out a decade ago. its also why you shouldnt ever deprime a reversed primer. i know lots of people do it but it only takes one.
i use one of these:
the rcbs tool above seperates the primer being worked with totally form the tube so if the case being primed does go off it doesnt set off the ones in the tube they are too far away.
or the primer system on my dillon 650.
friend of mine had a detonation in his dillon 650 it set off all the primers in the tray and some in the tube. but thanks to dillon's design no primer shrapnel got loose and dillon replaced the damaged parts.
anytime you prime you should be wearing goggles. the little buggers are STRONG