.357 SuperMag
Based on the .357 Magnum cartridge, a revolver or single-shot pistol designed for the .357 SuperMag can also fire .357 Magnum, and .38 Special rounds. The .357 SuperMag is essentially the same cartridge as the later-named .357 Remington Maximum that was jointly developed circa 1982-1983 by Sturm, Ruger & Company and Remington, the .357 Max brass being only 0.005" shorter than the .357 SuperMag brass, but identical in all other dimensions. Ruger, as well as Dan Wesson, introduced revolvers in this cartridge, followed shortly later by Thompson/Center in their single-shot Contender. Due to flame cutting of the top strap of revolvers when shooting cartridges loaded with 125 grain bullets, Ruger discontinued their revolver in this cartridge after a short production run. Dan Wesson provided a second barrel to customers, but this failed to address customer fears, and the cartridge remained popular only in the T/C Contender. Remington then dropped this cartridge from production, although brass is still manufactured for reloaders every few years. The next run of new unprimed brass by Remington for reloading this cartridge is expected in 2009.
Because there is so little difference - practically none - they are the same.
Good Luck and Good Shooting