The SASS rules regarding revolver calibers are: - Must be centerfire calibers of at least .32 caliber and no larger than .45 caliber or percussion calibers of at least .36 caliber and no larger than .45 caliber.   - Must be in a caliber commonly available in revolvers. Examples include, but are not limited to, .32-20, .32 Magnum, .357 Magnum, .38 Special, .44 Magnum, .44- 40, and .45 Colt. SHB p.37   Since Ruger, Colt, and other revolver manufacturers have been producing revo