I had a friend back in my teems that had the most "automatic" of these single shots I've ever seen. Every time he's pull the trigger the gun would then pop open and eject the spent shell. If he wasn't holding on or the tape had worn that held the forearm on it would them fall off as well. I used to give him quite a bit of "distance" when we were hunting.
Jim

The 2nd Amendment IS an unalienable right.