And now,
Style 3
Same as Style 2, but eliminates the magazine tube slot and barrel pin, and replaces them with a 5/8 - 11 threaded barrel channel, for aftermarket barrels to be used.
I didn't want to shrink the barrel recess anymore, since its already fairly small, so I had to make this design a box magazine fed only variant, as the tube magazine placement would get too close to the barrel threads.
CAD Video of Style 3:
http://www.youtube.com/watch?v=luKX7Cn48u0