Underwood's +P .45 Colt load sends a 250gr Hornady XTP jacketed hollow point at 1,400 fps, generating 1,088 ft-lbs of muzzle energy. Those numbers put it in the same energy class as hot .44 Magnum loads, which is remarkable for a cartridge that dates to 1872. The nickel-plated brass case feeds cleanly and resists tarnishing. This is strictly a heavy-frame revolver load: Ruger Blackhawk, Ruger Redhawk, Freedom Arms, and similar overbuilt guns. It should never be fired in Colt SAA-pattern revolvers, replicas, or any lightweight .45 Colt firearm.

The Hornady XTP bullet is a proven design that expands reliably across a wide velocity window. At 1,400 fps, the XTP will open up to about twice its original diameter while retaining most of its weight. Hornady designed the XTP with serrated jacket walls that control how fast the bullet mushrooms, preventing over-expansion at high velocities and ensuring the bullet reaches adequate depth. That makes it a better hunting projectile than generic hollow points, which can blow apart at these speeds.

This load is built for hunting medium to large game with a .45 Colt revolver. Deer, black bear, feral hogs, and elk at close range are all realistic targets. At 1,088 ft-lbs it hits harder than most .357 Magnum loads and approaches .44 Magnum territory. Handgun hunters who prefer the .45 Colt platform but want more energy than standard loads provide will find this is one of the most powerful factory options available. The trade-off is substantial recoil that demands a firm grip and practice to manage accurately.