The .500 S&W Magnum is a .50 caliber, semi-rimmed pistol cartridge developed by Cor-Bon in partnership with the Smith & Wesson "X-Gun" engineering team for use in the Smith & Wesson Model 500 X-frame revolver. The cartridge, along with the Smith & Wesson Model 500 revolver, was introduced in February 2003 at the SHOT show. The purpose of this cartridge was as a hunting handgun cartridge capable of taking all North American game species.
The .500 Smith & Wesson Magnum was designed from the outset to be the most powerful production handgun cartridge in existence at the time. Smith & Wesson product manager Herb Belin proposed the idea of developing the revolver and cartridge to the S&W sales team. With the backing of the sales team, the project was approved by S&W President Bob Scott. The ammunition would be developed by Cor-Bon and Peter Pi in partnership with the S&W X-Gun engineering team of Brett Curry Lead Design Engineer, Rich Mikuta and Tom Oakley. Eleven months later, on January 9, 2003 the team unveiled the S&W Model 500 revolver and the .500 S&W Magnum cartridge. According to Belin, the cartridge was designed from its inception to be substantially more powerful than any other production handgun cartridge before it. Cor-Bon would later go on to develop the .500 S&W Special cartridge.
The .500 S&W Magnum cartridge uses bullets that are .500 inches in diameter (.50 caliber, 12.7mm). The Smith & Wesson Model 500 revolver will accept both .500 S&W Magnum and .500 S&W Special ammunition; unlike other revolver cartridges, there are no firearms that will accept .500 S&W Special cartridges, but will not fire the .500 S&W Magnum.
The .500 S&W Magnum is a rimmed, centerfire cartridge. Initial runs of this cartridge used large pistol primers; Smith & Wesson switched to using large rifle primers to prevent the firing pin from piercing the primer when max loads or heavy bullets were used (bullets over 400 grains). The .500 fires at a maximum pressure of 60,000 PSI, launching projectiles ranging in weight from 275 grains to 500 grains at speeds ranging from just over 1,400 FPS to over 2,000 FPS. Most factory loads fire at pressures of around 50,000 PSI, and some handloads may use bullets heavier than 500 grains.