Id have to say i had an AD once when my MKIII 22/45 slam fired on me due to shimming the sear to far. But it was point down range per safety rules when racking the slide.
I had a lady taking the ccw course next to me last week at a public range and she racked the slide on a M&P 9mm and it fired as she dropped the slide as her finger was on the trigger. The RO heard about that one from me later.
I did get busted for being negligent with my benchrest rifle recently, But nothing went off.
I was out of state visiting relatives in WV and i had just returned from shooting and my uncle came to my other relatives house i was staying at and i wanted to show him my gun.
I go back in the house and retrieve it and hand it to him and say "Its empty" but didn't check.
Then i knew i did something wrong as i didn't clear the weapon after saying that a second later. He opens the bolt and out pops a spent .22lr case.
He says "Empty huh?" I about crawled under the porch and apologized.
IMO it could have been a live round just as easy as a spent round as it shouldn't have been there anyhow.
I learned a lesson the easy way that day with not even a round going off, But i felt like an IDIOT for my actions.
There are only 2 kinds of shooters; those who have had an AD, and those who WILL.
I believe this is true and should include ND also.
Its human nature to make mistakes, Its how we learn to correct them and hopefully live threw them not to make the same mistake twice.