History of US Military Sidearms

The Colt Single Action Army of 1873 served as the replacement for the 1860. It had a top strap to improve durability, and loaded spare cartridges in the side by opening up the loading gate. Also known as the Peacemaker, the 1873 SAA became one of the most common revolvers of the Old West and remains in production today.

The SAA served the United States military up until 1892. It was made in over thirty different calibers, including .45 Long Colt, .44-40, .32-20, .38-40, and .38 Long Colt. However, the .45 Long Colt version was by far the most common version and the one that saw military use. 

Today, the 1873 SAA remains popular due to the fact that it is very ergonomic and because of its association with the American West. It’s a timeless design that will never be forgotten. 

The Colt M1911 and M1911A1 are without question the most famous sidearms of the United States military. The M1911 was developed and adopted by the US army in 1911 as a replacement for their revolvers, and beating out the only other competitor in the form of the Savage 1907. The M1911 was ultimately selected because it was the only entry that went 6,000 rounds without a single stoppage, whereas the 1907 Savage had thirty seven failures in the same round count.

The M1911 served with distinction in World War I, where it proved to be a very reliable pistol. The M1911A1 was developed in the 1920s with improvements, including an arched mainspring housing and a shorter trigger. The M1911A1 was produced in great numbers during World War II, to the point that post-war production was cancelled as the army just continued to use the World War 2 made guns.

The Colt M1911A1 in .45 ACP continued to be issued and used throughout World War 2, the Korean War, and the Vietnam War. It was officially replaced by the Beretta M9 in 1985, but has never been totally phased out as there are still certain soldiers who continue to use it to this day.

Nearly three million M1911A1 pistols were issued to the United States army. As with the 1873 Colt, it remains a timeless design that will never be forgotten and will always be remembered as a part of America’s arsenal.

The first revolver made was the Colt Paterson of 1836, and several thousand were purchased by the United States government to help replace their aging flintlock pistols such as the 1775 Model. However, the Paterson was not as successful as Colt had hoped (mainly due to the fact that the weapon was not fully reliable and was underpowered), and the Paterson factory eventually closed. 

In 1847, Captain Samuel H. Walker of the Texas Rangers approached Colt with an idea for an ew sidearm that offered more power than the 1836 revolver. The result was the Colt Walker, a .44 caliber six shot revolver that to this day remains the most powerful sidearm that the American military has ever adopted. 

As with the Paterson, the Walker had issues. It was massive and heavy, and often had to be carried in a horse’s saddle. It also had weak metallurgy, and the loading lever was weak and would often come loose. A third of all Walkers were actually return to Colt for repair. 

The Colt Model of 1860 revolver was greatly improved over the 1847. It also fired the .44 caliber ball round, but with less powder so it was less powerful overall. However, it was also much lighter and smaller, and therefore easier to wield.

Hundreds of thousands of 1860s were issued to the US military during the US Civil War, but it continued to be the issued sidearm up until 1873. After the war, the weapons were converted to fire metallic cartridges, which were much safer and faster to reload. 

One issue with the 1860 was its durability, as it had no top strap and the frame was instead secured with a cylinder pin. This reduced bulk and weight, but at the expense of durability. 

The Colt M1917 and Smith & Wesson M1917 revolvers were adopted by the US military during World War 1 as a supplement to the M1911 Colt pistol, which could not be made in high enough numbers. The M1917 revolvers fired the .45 ACP round just like the M1911 Colt, and were loaded with moon clips since the .45 ACP is a rimless cartridge. The rounds could be loaded individually without the moon clip, but would have to be ejected using a pencil or cleaning rod. 

The M1917 revolvers were also issued in World War 2, but in far lesser numbers. Today, they are very valuable collectors items. They are noted for their large and intimidating size in order to accommodate the wide .45 ACP round.

The first ever sidearm used by the United States military was the Flintlock pistol Model of 1775. It was literally just an American-made clone of the British 1760, which meant that in the Revolutionary War the British and American Continental forces wielded the same pistols against one another. 

Specifically, the Model 1775 was a .62 caliber flintlock with a smoothbore barrel. It was well known for its accuracy and became the standard sidearm for officers. All in all, over 2,000 Model 1775 pistols were issued during the Revolutionary War, and thousands more were made and issued to the American military up until the invention and widespread use of of the revolver in the 1830s and 1840s. 

The Beretta M9 was adopted in 1985 as the replacement for the Colt M1911A1 in .45 ACP. It narrowly beat out the SIG Sauer P226, mainly due to cost reasons as Beretta came in at $1 less per pistol. The M9 was chosen at a time when the decision was made to switch to a large capacity 9mm pistol that could be standardized with NATO.

The Beretta M9, or the 92FS for the civilian market, has proven to be an excellent pistol. Early issues were sorted out and the pistol has served in all major conflicts the US has been involved in since then.

The M9 is a double action single action pistol with a 15 round magazine. The design is based very heavily off of the proven Walther P38, which serve as the German army sidearm from 1938 up until 2004. Later versions of the M9 included the M9A1, which came with a picatinny rail on the frame for the Marine Corps, and the M9A3, which Beretta had hoped would succeed the original M9, but was instead replaced by the SIG Sauer M17.

The SIG Sauer M17 and M18 pistols, or the military designation for the SIG Sauer P320, serve as the military’s current sidearms as they replace the older M9 pistols. 

The M17 has a longer barrel and slide, while the M18 is more compact. The M17 will be issued to the army, and the M18 to the Marine Corps and to the Air Force. Time will tell as to how well the M17 and M18 will hold up, but so far the reception from service members has been very positive. 

The P320 pistol is unique because it is a truly modular handgun. You can remove the gun assembly from the frame and then swap it out between pistols for convenience, which is one reason why the military decided to go with the weapon. Standard capacity is 17 rounds of 9mm.

The Colt Model of 1892 served as the replacement for the 1873. While definitely not as aesthetically pleasing as the 1873 SAA, it still featured a number of critical improvements. Most notable was the swing out cylinder, which facilitated faster reloading.

The biggest limitation to the 1892 was its caliber - the .38 Long Colt. While the .38 LC offered less recoil, it also offered less firepower. Many American soldiers find it underpowered in combat, and as a result, the US Army actually began issuing 1873 SAAs again with their .45 LC cartridge for a time until more powerful guns were adopted later.