When i first started using my Hornady hand prime tool, i'd get going to fast and put one in side ways now and then when doing large batches. After carefully pushing it back out after neutralizing it once or twice, i finally took one outside and crushed the liveing #$% out of it till i could remove the case. No bang, hmmm. I then deliberatly started 10 sideways and crushed them flush into the case, no bang.... Unless you give them a mother of a wack (sharp and fast, i can't with a hand primer tool) they don't seem to want to go off. Saftey glasses are always a good idea, but its a primer, not half a stick of TNT...Same goes for pushing them back out with a decap/size die, have yet to have one go off. Maybe if i flung the ram up i could, but i figure i'd be more likely to bust the de cap pin. And even then the base of the cartride/primer would vent down the ram.