[Also posted in Handguns -- sorry for repeat, but got no answer there]
Looking at all the interesting little CF .22s for pistols these days, from the Chinese 5.8 x 21mm to the FN 5.7 x 28mm. Something in this range looks like it would a ball for critters in the jackrabbit-to-coyote range, or just for general "I gotta new toy" range fun.
Clearly the FN round is too long for the Colt, but since the 9x25 Dillon seems to fit, how about a necked down 7.62x25mm Tokarev, also known as the 22 Reed Express? Seems like, with some care in bullet selection (I'd think 35-40 gr would be best), you could keep the OAL manageable. Plus, with the same rim diameter as a 9mm, you should be able to pack 18rds in a double-column version of the Reed round, and use 9mm mags. Lots of 200yd gong ringing before reloading...
(I have seen the .224 Boz, basically a 22/10mm, which I think is just too overbore for a 5-6" bbl. The guys who marketed the Boz claimed functionality in a 1911, but thus far I've received no replies from all my transmittals to them, so I have some doubts in their veracity.)
Since there never really seems to be anything new in gunnery, I'm sure some reputable soul out there has already done this (or something like it) in a 1911. Anyone know of a pistolsmith who's tried? Reed site says barrels will be available soon for CZ52. I love my CZ and I'll get one of these tubes, but the grip angle is weird and I would to set one up in a 1911.
The Reed Express should manage 2450-2500 with a 35 gr, 2250-2300 with a 40 gr (w/ 6" bbl and fully-supported chamber), outpacing a .22 Mag fired from a rifle by 10-15%. Fun!!
No, I'm not looking to punch through body armor, and I don't want another FN Five-seveN wunderpistol with magic powers. And yes, I already have a .45 (along with a 400 Cor-Bon barrel) and a 10mm, so I have the big stuff covered.
i was thinking about this same thing for a project. however i have a bunch of other projects on the table to complete before i even think of doing one of these. make sure to post if you pull it off so i can copy you in the future.