Underwood loads this .45 Colt cartridge with a 255gr lead semi-wadcutter gas check bullet at 1,000 fps, producing 566 ft-lbs of muzzle energy. The semi-wadcutter profile has a flat nose with a stepped shoulder that cuts clean, measurable holes in paper targets. The gas check is a small copper cup crimped onto the bullet base that seals the bore and prevents hot gas from melting lead off the bullet. That means less leading and more consistent velocities, especially at this speed where bare lead can start to cause problems.

The 255gr weight is the classic .45 Colt bullet weight, matching what the cartridge was originally designed around. At 1,000 fps it runs about 100-150 fps hotter than typical cowboy loads but stays well within standard pressure limits for any modern revolver. The gas check design lets Underwood push the velocity higher than a plain lead bullet would tolerate without fouling the barrel. Shooters get the accuracy and clean-cutting holes of a lead SWC without the maintenance headaches of heavy leading.

Range shooters and target competitors who want a heavier-recoiling practice load will find this useful for building skill and trigger control. The 566 ft-lbs of energy also makes it a reasonable field load for plinking at steel targets, where the heavier bullet produces a satisfying ring. It works in both revolvers and lever-action rifles chambered in .45 Colt. Shooters who reload may appreciate the gas check design as a benchmark for their own handloads, since Underwood's factory velocities are consistently within advertised specs.