Yeah, I'm only speaking to possibility, not probability. We might, with effort, be able to engineer a situation where there were two projectiles and the leading one exits while the trailing one does not.I think that's what I said only I used the Cliff Notes version.
Coincidentally, my son experienced a rare failure of S&B 9mm 115 grain FMJ ammo the other day, a kind of failure that usually only happens to reloaders: they'd jammed a primer in sideways. My son hadn't noticed. The primer ignited, unfortunately, but fortunately the powder did not. Didn't damage anything, but that residue of the burnt primer compound was hard to clean off the half of the bolt face where it deposited.