A magazine of a pistol for cartridges of the caliber .22LR with a case rim, consisting of a hollow magazine body for receiving the cartridges in two rows, a stub-like base plate, a feeder slidably guided in the magazine body, a compression spring between the feeder and the base plate, which base plate has a bore as do the two side walls of the magazine body comprise openings, all of which are formed by a transversely extending bolt, wherein the upper end region of the magazine body forms a constriction in which two rows of cartridges are brought together into one. The side walls have inwardly directed corrugations running longitudinally over their entire height, which merge with guide ribs in the upper region.