This storied Old West revolver round is still alive and well in the 21st century.
When people talk about the Colt .45, whether they know it or not, they're referring to a specific gun and a cartridge. In addition to the original Colt Peacemaker, it's a reference the .45 Long Colt cartridge, also simply called the .45 Colt or .45 LC.
It's a rimmed straight-walled handgun cartridge that was introduced in 1872, though it later saw use in plenty of lever-action rifles and carbines.
Back then, it was a black powder revolver cartridge developed for the Colt Single Action Army Revolver, which the U.S. Army adopted in 1873. It almost switched to the .45 Schofield made by Smith & Wesson for its Model 3 revolver, but logistics and supply chains kept them in the .45 Long Colt business for 14 years.
The .45 Long Colt was a product of both Colt's Patent Firearms Manufacturing Company and the Union Metallic Cartridge Company, both of which called Connecticut home.
When the .45 Long Colt and the SAA came along, they replaced the Model 1871 Remington Single Shot pistol and a variety of cap-and-ball revolvers that had been converted to use metallic cartridges.
In 1892, the military went with the doomed and underpowered .38 Long Colt, which didn't last long. In 1909, the .45 Colt New Service Revolver took its place using the .45 M1909 round, which was nearly identical to the .45 Long Colt. It only had a larger rim diameter, which prevented it from being loaded in SAA revolvers or other ejector-rod guns.
In 1911, John Browning's M1911 semi-auto pistol and the .45 ACP replaced both.
Today, the .45 Long Colt is still popular, particularly among cowboy action shooters, typically chambered for single-action revolvers and lever-action rifles.
It also got a big boost about a decade ago when the Taurus Judge and S&W Governor revolvers debuted. These firearms can fire both .410 shotgun shells and .45 Long Colt centerfire ammo from the same cylinder. The Judge has become quite popular, with over a dozen models in the line. Bond Arms also makes a number of Derringers chambered for the ammo combo.
Subsequently, a number of ammo companies like Federal and Hornady began introducing self-defense .45 Long Colt handgun ammo with modern hollow-point bullets.
The .45 Long Colt also set the stage for several other rounds, namely the powerful .454 Casull. A revolver chambered for .454 Casull will fire .45 Long Colt, as well as .45 Schofield.
The even more powerful .460 Smith & Wesson cartridge is an elongated version of the .45 Colt and the .454 Casull.
The modern .45 Colt is a popular hunting load for deer and black bear, and heavier handloads are more powerful than a .357 Magnum and approach the ballistics of a .44 Magnum. Winchester, Marlin, Henry, Chiappa, Rossi, Uberti and Cimmarron all produce lever guns in .45 Long Colt.
You can find .45 Long Colt ammo with JHP, flat nose, and spitzer bullets for a wide variety of applications.