Guy named Lee Martin of single action pro boards site created cartridge called .257 Jackrabbit based on cutdown .25/20 case in order to work in Ruger Single-Six.

Probably larger than your goals but it sounds like it could be a CF reincarnation of Keith's pet .25 Rimfire. Cat Sneeze to supersonic potential in Single Shots & handguns.


�When in doubt, I whip it out.� Uncle Ted
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