I believe the longest cartridges in a revolver with a barrel length under six inches are unable to effectively burn the powder and achieve great velocities. I own a S&W 460V with a five inch muzzle brake equipped barrel. Shooting 454 Casull it probably comes out close to equal when using full out 460 S&W magnum in that short five inch barrel. But it is able to shoot 460 S&W magnum so I do.