Dog,
Those look like way too much fun. I have a couple of questions, as I have followed Jason's thread, and I am hoping to summarize what might work for an AR pistol, as I have a "pistol" lower coming.
First, the Model one gun appears to be a 22 LR upper, or at least converted. Is it a dedicated 22LR? If it is a 5.56 with a Ceiner insert, how is it performing with both (either). I am not sure whether Model 1 Sales' units have been reworkied with the "new" 1911 spring fix, or whether you had to tweak it. How is the Ceiner 30 rounder working?
I would presume that the lower gun is working fine, as the recoil system is a standard type. Is this the case?
Also, have you tried the Bushmaster pistol system? There was information on it in Jason's thread, and a query, but I could find no replies.
I do think that I am gonna build a pistol of some caliber, I have not yet decided what to do. I have thought about a 458 or 7.62, but I am leaning towards the 223/22LR combo.
Thanks,
Craig
Edited to add: Perhaps you should have included one of your rifle length barrels in the picture to go with the lower with the rifle stock, for the ATF ya know ;^)