The .38 Long Colt Ammo, also known as the .38 LC Ammo, a cartridge that used black powder, was designed and introduced into the markets in 1875 in the United States. The United States Military adopted the .38 Long Colt Ammo as a standard military cartridge in 1892. The .38 Long Colt Ammo is slightly more powerful than the .38 Short Colt Ammo. These cartridges differ in length, bullet diameter, weight, and design. The .38 Long Colt Ammo uses a .357-.358 in the cartridge; this way, the bearing surface and lubricant are entirely contained in the casing. However, the .38 Long Colt Ammo proved to be highly ineffective in wars as it was unable to deliver satisfying performance in the Philippine-American War. The .38 Long Colt Ammo remained the US Army's primary cartridge for revolves until the introduction of the .45 M1909 Ammo in 1909. The .38 Long Colt Ammo has an overall length of 26.2mm, and the bullet diameter measures 9.1mm. The 150-grain bullet load is the heaviest variant of the .38 Long Colt Ammo, which can travel at a velocity of 777 feet per second while creating an energy level of 201 ft.lbf.
Colt produced the .38 Long Colt Ammo in 1892.
The US Army has mainly used the .38 Long Colt Ammo for military purposes. Later it was used for target practicing and sports but was abandoned after the .38 Special Ammo was introduced.