I've had two AD, ND, whatever you want to call it!
First was with a High Standard 20ga. shotgun. An older pump shotgun, was out hunting and the safty just didn't feel right? I pointed the muzzle in the air, and reapplied the safty. Began pulling the trigger just to see if it would go off. About the third pull, the shotgun let fly..BOOM.. scared the crap out of me. I promptly got that fixed!
Years back, long ago, had been hunting with some of my high school buddies. Was cleaning the junk out of my pickup the next day, and found a JC HIggins bolt action 12ga. left in my tool box! Wasn't mine, wasn't sure who's it was.
I called my friends, and nobody claimed the gun!? I thought "what the heck", and tried the shotgun out on some starlings in a tree. Worked fine for the first couple shots. Starlings came back for me, and I prepared to give it to them. Worked the bolt on the JC Higgins and KA-BOOM!! Gun goes off as soon as the bolt closes. Another scare the crap out of me incident that involved the gun pointing in a safe direction!
I've been lucky, my two incidents were nothing. I've been involved in a couple other ND incidents that could have been more than awful!
Was living in Louisiana and had a couple coworkers come over to drink beer after work. One of these guys had just bought a .357 mag revolver. He went out to his car and got his new revolver to show us. My coworker and I were sitting on the sofa, and the new gunowner was in a separate chair to one side. He was scoping out his new gun and just as the two of us leaned forward to pick up our beers, his gun goes off! Bullet went behind both of us sofa sitters and passes through a wall to slam into the side of a kitchen stove! Bullet stopped at the stove, but put a huge dent in the side, plus enamal kept popping off around the bullet crater for 20 minutes afterwards to virtually de-nude the entire side of the stove! He got ran off to never enter my house again. Scared me real bad, would have likely killed us both if we hadn't reached for our beers at the same time!
Another incident involved myself and a friend stopping to visit one of my friends friends. Talk turned to guns and the homeowner went to get his new Winchester model 70 in .270 Winchester. We chatted a bit and admired the rifle, all good. The fellow had placed his rifle with the muzzle against the floor and the gun's butt on the sofa, like you might travel in a pickup with the gun. The rifle must have been loaded, because the guy pulled the trigger and KA-BLAM!!! We all go deaf!
The carpet on the floor rose up like a sudden volcano from the blast. Almost tipped over the coffee table! The homeowners cat literally ran around the room on the wall!! and busted out the front door! We left as the guys wife started eating his ass! Enough of that crap!