If this is the early version of the Model 63 semi auto, You will have to pick a single cartridge. Each has a different caliber marked on the barrel. 22 Long Rifle, 22 Short, and I think a 22 Rim Fire Special ( a little larger 22 rim fire) None interchange. Some where later on, I think Model 190, a semi auto that handled all three semi automatic cartridges ( late 60s or 70s ) Alum receiver, as was a Remington that did all three .22s. 22 Short, Long, and Long Rifle.