.45 Long Colt

The .45 Colt — often called .45 Long Colt to distinguish it from .45 ACP, though “Long Colt” was never its official designation — is the cartridge that armed the American frontier. It was designed in 1872 for the Colt Single Action Army revolver, the gun that became known as the Peacemaker. If you’ve ever watched a Western and thought “that looks right,” you were thinking about this cartridge. It’s still in production, still popular, and still one of the most capable big-bore revolver rounds you can carry in the field.

The .45 Colt was developed in 1872 by Colt’s Patent Firearms Manufacturing Company and the Union Metallic Cartridge Company for adoption by the U.S. Army. It was chambered in the Colt Single Action Army, adopted in 1873 — the same year the cartridge was approved. Together they were the standard U.S. cavalry sidearm for over two decades. The .45 Colt became the defining cartridge of the American West, carried by lawmen, outlaws, soldiers, and civilians across the frontier. When single-action revolvers faded from military service, the cartridge never entirely faded — it just found a civilian audience that never got tired of it.

Standard commercial .45 Colt loads push a 250-grain bullet at around 860 feet per second for approximately 410 foot-pounds of energy. That’s comfortable, controllable, and effective. But the .45 Colt’s story doesn’t end with standard loads — strong modern revolvers from Ruger and Freedom Arms can handle much hotter handloads that push 300-grain bullets past 1,200 fps and deliver over 1,000 ft-lbs of energy, putting the .45 Colt in serious hunting territory. The gap between cowboy loads and hot hunting loads in this cartridge is enormous, which makes it one of the most versatile big-bore revolver rounds available.

Cowboy Action Shooting is the obvious one — the Single Action Shooting Society (SASS) has made the .45 Colt the most authentic choice for that sport, and single-action revolvers in this caliber are everywhere in that community. Handgun hunting, particularly in strong Ruger Blackhawk or Redhawk revolvers loaded hot. Self-defense for those who carry a Taurus Judge or Governor, both of which chamber .45 Colt alongside .410 shotshell. And lever-action rifles — the .45 Colt is a natural in lever guns and makes an outstanding ranch rifle round for everything from coyotes to hogs.

Pros: genuine historical character, excellent versatility across standard and heavy loads, outstanding performance in lever-action rifles, and an inherent cool factor that no marketing department could manufacture. It’s a legitimate defensive and hunting round dressed in frontier clothes, and it delivers. Cons: single-action revolvers are slower to operate and reload than double-action guns, standard pressure factory ammo is relatively mild if you want maximum performance from the case, and the caliber is somewhat less widely available than 9mm, .45 ACP, or .38 Special. You won’t find it at every gas station. You will find it at any decent gun store.

The .45 Colt was so effective as an Army cartridge that when the government later tried to replace it with the .38 Long Colt, the results were poor enough that it helped drive the development of the .45 ACP and ultimately the 1911. In a roundabout way, the .45 Colt is the ancestor of the .45 ACP — the Army simply refused to downgrade from .45 caliber after what the .38 Long Colt taught them in the Philippines. The old frontier round still matters.

Arms East carries .45 Colt revolvers, ammunition, and lever-action rifles. Whether you’re building a Cowboy Action setup, looking for a capable hunting handgun, or just want something that connects you to a genuinely important piece of American history, we’ve got options worth looking at. Come in and hold one. The single-action revolver is an experience that doesn’t translate through a screen.