What you have is not a .22 MRF, but a .22 Jet (model 53), which is essentially a .357 magnum case necked down to 22 caliber. It is a centerfire cartridge. You also have the inserts for the cylinder to be able to shoot .22 LR.

With the Jet cartridges the chambers have to be meticulously clean and dry. If not you may experience cartridge setback, which will tie up the gun.

These are collectible, but many owners still shoot and enjoy theirs.

Adios,

Pizza Bob

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