I'll share my experience - Even though it wasn't my fault!
Happened when I was a kid, somewhere between 6 and 8, but I still remember it. My dad and I were out at the range, and we had several .38 Special guns with us, trying out some handloads. We had two batches of ammo, some +P stuff that we were firing out of revolvers, and some light loads we were shooting from a converted 1911. Good bit goes by, and I'm chewing paper through the 1911, no problems, but you can probably see where this is going. My dad is loading up mags for me as I'm firing, critiquing my shots and grouping (We start young in my family... At this point I had already been shooting for a couple years, I started at about 5)
Slide in a fresh mag, drop the slide, aim, take the shot, and kB! Massive detonation. 1911 falls to the ground, and I'm screaming. Sure enough, a simple mistake, and the +P stuff had been loaded into the 1911. The tiny exposed portion of the cartridge couldn't handle the high pressure loads. It detonated in the chamber and exploded down into the grips, blowing the custom wood grips in two, sending splinters, burning powder, and hot gas back into my face. There was gunpowder embedded in my hands and face, slivers of shrapnel everywhere. And a very traumatized little boy who would "trigger-lock" on the line for a good 6 months, year, not sure how long it was before I could overcome the fear and fire a gun again, but it took a while. I wasn't scared handling them and had no apprehension getting ready to fire one, but my brain just flat out refused to tell my finger to pull the trigger for quite some time after that.
When the cartridge was retrieved, it was impressive, to say the least. There was maybe a 2 or 3mm semi-circle blown out just above the butt of the case, and I mean this thing was
perfect. You couldn't have machined a cleaner edge out of this thing. No bulging, no ragged edges, it looked like it had been sawed half-through by the best machining tools known to man.
Worst of all - The damn bullet didn't even hit paper! Years of psychological trauma, and no bullseye to show for it!
I still say the thing eeked out of the barrel with just enough velocity to clear and fell short on the ground somewhere, though, damnit.