Uwe Janz makes Magnum revolvers with interchangeable barrels, cylinders, and calibers in Bad Malente / Holstein, Germany. His revolvers are based on the action developed in 1979 by Willi Korth, scaled up to accommodate big bore calibers. They come in three frame sizes—EM, E, and MA. The EM frame, sized similarly to the S&W N-frame, can be fitted with cylinders and barrels ranging from .22 LR to .44 Remington Magnum, with barrel lengths ranging from 2½" to 12". The intermediate E frame will accept the same barrel lengths, and cylinders chambering rounds ranging from the .22 LR to the .454 Casull. The largest MA frame, sized similarly to the S&W X-frame, accepts barrels ranging from 4" to 12" in length, with cylinders chambered in .460 S&W Magnum or .500 S&W Magnum. Overall, there is a choice of ten barrel lengths, and compensators can be fitted to all but the shortest 2½" barrel. For the quick-change frames five calibers and no fewer than twelve chamberings are available: .22 (.22 LR and .22 Winchester Magnum), .32 (.32 S&W Long and .32 H&R Magnum), .38/.357 (.38 S&W Special, .357 S&W Magnum, and 9mm Para), .44 (.44 S&W Special and .44 Remington Magnum), and .45 (.45 Colt, .45 Winchester Magnum, and .454 Casull), with cylinder capacity varying from five rounds in .454 Casull, six rounds in .44 Remington Magnum, .45 Colt, and .45 Winchester Magnum, seven rounds in .38 S&W Special and .357 S&W Magnum, and eight rounds in .22 LR. All grip frames are dimensioned identically to the round butt S&W N-frame, and accept the same grips. Each revolver is made to order. Many custom options are available.