The 375 SuperMag is something quite different. It was developed for metallic silhouette shooting by IHMSA president and famous big-game hunter Elgin Gates. Originally factory brass was available, but the supply for the most part has dried up and now brass is made using the 375 Winchester brass. It must be cut to 1.610″ and then run thru a sizing die and trimmed.
The .375 Super Mag is something quite different. It was developed for metallic silhouette shooting by IHMSA president and famous big-game hunter Elgin Gates. This “factory wildcat” consists of the .375 Winchester Big Bore rifle cartridge case shortened from its original 2.020 inches down to 1.6 inches for more efficient use in a handgun. The theory behind this cartridge was that one could have a cartridge that was ballistically somewhat more powerful than the .44 Magnum (the favorite in IHMSA’s revolver class) that would fire a bullet of better aerodynamic characteristics and greater sectional density. Such a bullet would give superior downrange ballistics coupled with a longer “hang time” on the silhouettes than the .44 Magnum. The .375 Super Mag was first developed using a Contender barrel; Gates subsequently persuaded Dan Wesson and United Sporting Arms to chamber revolvers for this cartridge, thus bestowing a degree of legitimacy on the wildcat kitten.