[Theohazard]

I've seen one, disassembled it, and played around with it a bit, but that's it; I never fired it. It seems like it's a design without much room for error. The cartridge is pulled backwards from the magazine at the fastest point in the slide's movement, the beginning. To achieve this without ripping parts of the case rim off, the initial slide movement has been slowed down, I believe mostly by a rather lengthy rotating barrel lock-up. In addition to having more moving parts, it seems to me like it would be finicky about feeding different pressures of ammo: too much pressure and the feed claw loses its grip on the case rim; too little pressure and it can't overcome the lengthy unlocking mechanism.

I'm not discounting the Boberg at all, it's a pretty cool design. But the benefit (the ability to fit a longer barrel into a shorter weapon) doesn't seem to be worth it unless it ends up being as reliable and durable as a traditional design.