.45 Colt

The .45 Colt cartridge was developed by the United States Army at Frankford Arsenal in 1872 as an improvement of the British .476 Eley to replace the standard issue Smith and Wesson .44 round in the famous Colt Single Action Army, often known as the Peacemaker single action revolver. The United States Army adopted the cartridge in 1873 and it remained in use until 1877 when the army went to the M1877 ball revolver load. The new round was shorter than the original in case length and used a reduced powder charge of approximately 30 gr of black powder vs the 40 gr in the original. All Colt army revolvers were still chambered to fit the longer .45 cartridge case. In 1892 it was replaced by the .38 Long Colt. The United States Army briefly reintroduced the .45 Colt in 1902 for use in the Philippines, but it was made obsolete by new automatic pistols firing .45 ACP.

Cartridge loads
Originally a blackpowder cartridge, modern loadings use smokeless powder. The original blackpowder loads called for 30 to 40 gr of blackpowder behind a 255 gr lead bullet. Original loads developed muzzle velocities of up to 1000 feet per second (305 m/s), for a muzzle energy of 566 ft·lbf (766 J.). Because of this, the .45 Colt was the most used cartridge of its time, preceded by the .44 WCF (also known as the .44-40 Winchester). It was said that the round was powerful enough to knock a man to the ground in a single shot. It was also extremely accurate (for a pistol of the time). With careful handloading the original loads can be safely replicated using modern powders.

Today's standard factory loads develop around 400 ft·lbf (542 J) of muzzle energy at about 860 feet per second (262 m/s), making it equivalent to the .45 ACP. There are also Cowboy Action Shooting loads which develop muzzle velocities of around 750 feet per second (230 m/s).

Some very heavy handloads and some cartridges loaded by small companies are around that put this round in the same class as the faster .44 Magnum. Such loads are not issued by major companies such as Winchester Repeating Arms Company and Remington.

These loads cannot be used in any original Colt Single-Action Army, or any replica thereof (such as those produced by Uberti or Beretta, and guns like the Taurus Gaucho, or Ruger New Vaquero.) They should only be used in modern large-frame revolvers such as the Ruger Blackhawk, any gun firing the .454 Casull cartridge, or single-shot hunting pistols and modern rifles with strong actions (such as the Winchester Model 1894, Marlin Model 1894, and new clones of the Winchester Model 1892) chambered for the cartridge.

Uses
Over 133 years after its introduction, the .45 Colt still enjoys a wide range of uses. The .45 Colt makes a good hunting load, within its range limitations. Standard loads are good for animals the size of deer and black bear, and the heavier hunting loads will take about the same range of big game animals as the .44 Magnum, but less effectively, as the bullets of the factory loads move comparatively slowly and have a steep trajectory making long range hits harder. A two-barrel derringer is also still sold that is chambered in .45 Colt, and these derringers will also chamber a .410 bore shotgun shell without any modifications being required. Similarly, .45 Colt cartridges are still occasionally fired in .410 bore shotguns by U.S. farmers needing to kill a mule or horse humanely. However, the most popular use for the .45 Colt today is in Cowboy Action Shooting, where the round is fired from either originals or replicas of the 1873 Colt Single-Action Army or similar guns of the period.

Comparisons with other cartridges
The .45 Colt is the basis for the much more powerful .454 Casull cartridge, with the .454 Casull having a slightly longer and stronger case. Any .454 Casull revolver will also chamber and fire .45 Colt, but the inverse is impossible due to the Casull's longer case.

The .460 S&W Magnum is an even longer version of the .454 Casull and the .45 Colt. Likewise, .460 Magnum revolvers can also chamber and fire the two lesser calibers, but again, the inverse is impossible.

The .45 ACP round produces inferior game killing ability, as it cannot use heavyweight bullets. It uses a much shorter overall cartridge length, with faster burning powders and higher chamber pressures, allowing it to be used in more compact autoloading pistols and submachine guns. Because of this, the .45 ACP is superior to the .45 Colt for military purposes.

Original name
The designation ".45 Long Colt" originated amongst military personnel to prevent confusion with the smaller .45 Schofield. It has become a widely used alternative name for the cartridge, and adopted by Colt for use in designating the chambering in it's own Single Action Army revolvers.

Categories
Cartridge:handguns