This happened to a friend of mine:
A friend of mine about a month ago purchased some really inexpensive hangun (9mm Luger) ammo at a gun show. He complained that he was having feeding probs and it was "oozing"
He also couldn't get a live round unjammed. So, I said I'd take a look at his gun. Weapon is a Springfield XD 9mm sub-compact (same gun I had until a little while ago).
When he racked the slide back and let it slide forward to show me what was going on, the weapon discharged into the wall. Of course, following gun safety it was pointed down and towards a relatively "safe" surface.
The slide was NOT closed fully when the gun went off (out of battery).
His finger was NOT on the trigger. I was there and CLEARLY saw no contact with the trigger. The case did NOT explode (amazingly enough).
When I later calmed down I looked at the case. There was still a large WAD of UNBURNED powder in the case.
The primer burned a hole through part of the crimp that holds it in place, showing an uneven high-temperature burn-through.
I took some of the ammo and emptied out the powder (while using explosion-resistant glove box I may add). I dropped the empty case with live primer from less than 6" onto steel plate and the primer went off. I shook it for a little over 3 min. in a mechanical shaker I have (I do product FMEA for a little extra $ + fun), it went off. When acceleration was pushed to -9.3g, detonation occurred.
My conclusion is severalfold:
1. Avoid ammo that is unmarked surplus junk of unknown DATE CODE.
2. Expired corrosive ammo is dangerous.
3. This was likely caused my a corrosion problem and bi-metal interaction between the primer and the lacquer or sealent on the case.
4. Follow gun safety always: AD's often can occur when the slide is slammed forward because the firing pin block can be penetrated by the firing pin, or shock-sensitive ammo (this case) can be set off.
What I could not figure out:
1. Why would some of the powder burn, but not all of it.
2. Exact chemical interaction that over time could have caused this very dangerous condition to occur.
3. Why the flame was so uneven in the primer that it did not just go throught the flame hole (where it is SUPPOSED to go) but actually BURNED a second hole right through the case.
BTW, his gun is completely okay, as checked by a gunsmith. I still think it should be sent back to Springfield just to make sure, but that is out of my hands.
All I know is this stuff behaved more like Nitroglycerin or Red Fuming Nitric acid than any primer I've ever seen before.
Sorry I don't have any pics of this, it would be much better to show you guys visually.
Note: THIS IS NOT A SPRINGFIELD XD PROBLEM: THIS IS A VERY DANGEROUS AMMUNITION PROBLEM THAT CAN CAUSE LOSS OF LIFE OR KB'S!