I think the BATF regs are probably what've kept the idea of making one just that-an idea, for most people, myself included, but it's sorta a fun thought exercise. By the way, they did make a 9mm version during Vietnam, called the "deer gun" probably for secrecy reasons. It was supposed to be given to resistance movements against the VC/NVA infrastructure. I've actually seen pictures of one, I think the breach is screwed on rather than sliding closed, but it's pretty much the same gun, and was unrifled as well. By the way, is that specimen in the pic yours, and what did you have to do to make it legal? One would think that an original would be on the CRF list by now.
Mal-"Jayne, how many weapons you plan on takin', you only got the two arms."
Jayne-"Well I just get excitable as to choice-like to keep my options open."