Super magnum
A super magnum is a longer and/or more powerful version of a "magnum" cartridge. Although the term "super magnum" typically refers to a handgun cartridge, created by lengthening an existing straight-case design, it can also refer to a rifle cartridge, such as the .17 Winchester Super Magnum (WSM). In this case, it simply denotes that it is of greater power than existing "magnums" of similar caliber, similar to other designations such as "Remington Ultra Magnum". The most widespread of these cartridges are the "SuperMag" family of super-magnum handgun cartridges that were proposed and tested by Elgin Gates in the 1970s.
Gates tested super magnum cartridges in .357, .375, .44, .45, .50, and .60 caliber. Gates' SuperMag cartridges are all 1.610 inches long—about 3⁄10 of an inch longer than a "standard" handgun magnum (i.e. .357 Magnum, .41 Magnum, and .44 Magnum, which are all the same length)—and use the same bullets as the original magnum cartridges. The extra powder capacity can increase muzzle velocity up to 30–40% over the original magnum rounds.
In the 1980s, Dan Wesson Firearms began to produce revolvers chambered for the .357, .375, and .445 SuperMag cartridges. In 2000, they added .414 Supermag, and .460 Rowland.
There have been other cartridges that were created by extending the length of existing magnum cartridges. Some of these are:
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.
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