The .454 Casull () is a firearm cartridge, developed as a wildcat cartridge in 1958 by Dick Casull, Duane Marsh and Jack Fullmer. It was announced in November 1959 by Guns & Ammo magazine. The design is a lengthened and structurally improved .45 Colt case. The new Casull round uses a small rifle primer rather than a pistol primer, because it develops extremely high chamber pressures of over 50,000 CUP (copper units of pressure) (410 MPa), which are rifle levels of pressure. It requires the use of a rifle primer to withstand those significantly greater pressures, blurring the distinction of it being a pistol or a rifle cartridge.
The round is one of the most powerful handgun cartridges in production. The .454 Casull round is primarily intended for hunting medium or large game, metallic silhouette shooting, and bear protection.
The Casull cartridges were originally loaded with a triplex load of propellants, which gave progressive burning, aided by the rifle primer ignition, resulting in a progressive acceleration of the bullet as it passed through the barrel.
See also
- .44 AMP
- .500 S&W Magnum
- 11 mm caliber
- List of cartridges by caliber
- List of handgun cartridges
- Table of handgun and rifle cartridges