- K Frame
Most firearms makers have special designations for their various frame sizes, but only the Smith & Wesson revolver frame designations seem to be in general currency these days. Modern Smith & Wesson revolvers are made on four sizes of frames: the J (small), K (medium), L (medium-large) and N (large). Formerly there was the I frame, superseded by the slightly longer J frame, and many years ago the petite .22 "Ladysmith" revolvers were made on an M frame. The K-Frame revolver is one of the most important innovations in Smith & Wesson history and was built specifically to handle the .38 S&W Special cartridge. Since its introduction, the K-Frame has been a favorite for military and police professionals as well as target shooters and enthusiasts. Today's K-Frame is available in .22 LR and .38 S&W Special.