Gun Fires Self
Well Jenning's has closed and reopened under at least 4 names, since they were Jenning's. They are to guns as the Yugo was to the car world. They were always at the low end of quality, and if shot very much wore out fast. I have seen them over the years usually jamming, and other odd things. But they weren't much to start with. One going into a slam fire mode does not surprise me, he likely bumped it just right when he laid it down. I've seen the same thing happen with Bersa's and a few AR's with worn disconnects (Back when a lot of cheap parts were made in China). "Cheap can be Expensive"