I've seen many relined UK rifles reproofed and stamped 220, and they were all chambered for the 22LR.

It's my opinion, based upon the different stamping, that the reline was originally done for the 22WRF cartridge in 1952 and then at some later date it was rechambered to the 22Mag. JMOFWIW.
Regards, Joe


You can lead a man to logic but you can't make him think. NRA Life since 1976. God bless America!