Even if you could adapt a barrel solution (perhaps with a barrel liner), you'd have to find some sort of magazine. While a .22 short round could probably work in the .25 acp mag, I don't know if the OAL of the .22 Long or Long Rifle would work in that mag (and I can't find dimensions on line.) And, as noted above, the extractor function would be hard to address.
More importantly, the ability of a .22 round to cycle the gun would be in question. You would probably need a different recoil spring, if the weight of the slide isn't too much for the round.
For what you'd have to do and spend to address these issues, I suspect you could buy a nice used TARGET .22 pistol.
Just save your pennies and shoot .25.
Last edited by Walt Sherrill; July 11, 2013 at 01:09 PM.