Years ago { and I mean years ago } there was a gun smith who converted Colt SSA to .22. Very labor intensive and a lot of parts had to be modified. It would be impractical to try and convert it back. I don't remember the name but I know it was written up in both American Rifleman and Gun Digest. This was prior to the Hawes, Rugers and so forth so it would have been the mid 50's.