i just read a thread in a gun magazine where the tester had a failure to fire a cartridge in a .380, so he waited 10 seconds before ejecting the shell.
i remember seeing warnings on ammo boxes that advised waiting longer periods of time than that, yet i have never experienced nor heard of a hangfire that was longer than a millisecond or a click- boom.

I believe the old rule use to be 20-30 seconds for a "hangfire". But like you I've never seen or heard of anyone actually having one. It either went bang or poof right now or it didn't do anything.

I saw a friend have one once but it was a second or less.

But even at that, that's plenty of time to rotate the cylinder out of line with the barrel, and that would not be pretty. I don't know what you do if you're in a gun fight....call a timeout?

Once had a batch of old military surplus ammo that was 98% "Bang", the other 2% were click... must be a dud.. bang. A good 2-3 seconds, just enough time to thing it was a dud then bang. Had my hand on the bolt about to open the action on the first one when it went bang. After that I just held on for a good ten count.

I had the same experience once. Firing surplus 7mm Mauser made in the late 1940s. Firing pin went "click" and I lowered the rifle from my shoulder and it went off. Must have been a 2-3 second hang fire.

I have had worse......some **** Argentine surplus 7.65 Mauser....the BEST of those rounds went off like a flintlock.....it was like "click..pffffsshhhss....BANG" the worst would hang up to 10-20 seconds. I had one go off on the ground, the bullet only went a few feet but the brass flew 10 yards away. It was a "lesson" that the round needs a chamber to contain the pressure, or else they just go "POP" and the bullet and brass seperate.

I ended up giving it to my local gun shop owner for free, telling him the ammo was ******* and he could pull the bullets out for reloading if he wanted to, I just wanted rid of that garbage!

I've also had one hangfire, about 35 years ago with some Remington 22LR. Just about the time when I was going to eject the round it fired, probably a good 5 second hangfire. Ever since then I keep the gun on target for a good slow 10 count and if I've feeling paranoid I'll wait for a full minute. It only has to happen once to scare the you know what out of you and teach you waiting is a very good thing.