.41 Long Colt

.41 Long Colt
Type	Revolver
Place of origin	United States
Production history
Designed	1877
Manufacturer	Colt's Manufacturing Company
Produced	1877 to 1939
Specifications
Bullet diameter	0.386 in (9.8 mm)
Case length	1.138 in (28.9 mm)
Case capacity	20 gr H2O (1.3 cm3)

The .41 Long Colt cartridge was created in 1877 for Colt's double-action "Thunderer" revolver. It was a lengthened version of the earlier centerfire .41 Short Colt, which was made to duplicate the dimensions of the even earlier .41 Short rimfire. The front of the bullet was about 0.406"-0.408”OD, the same as the case. The barrel was about 0.404”-0.406” groove diameter. The bullet lubrication was outside the case. At 0.386”-0.388"OD, The base of the bullet was smaller in diameter to fit inside the case. This is known as a "heel-base" or heeled bullet. The only modern heeled bullet is the .22 rimfire.

In the mid-1890s, Colt redesigned the cartridge. They reduced the entire diameter of the bullet to 0.386"OD and lengthened the brass case in order to put both the bullet and its lubrication inside the case. The overall length of both loaded cartridges was about the same. The barrel of the revolver was reduced slightly to match the more popular 38-40 at 0.400"-0.401” groove diameter (this was probably done for manufacturing reasons, not accuracy reasons). This meant that the outside diameter (OD) of the new bullet was smaller than the barrel’s bore, let alone its groove diameter. A hollow-base bullet can be dropped down the bore by gravity alone. The newer soft lead bullet was made with a large hollow base, like Civil War Minié balls. The intent was for the base of the bullet to expand with the pressure of the burning gunpowder to grip the rifling.

The original 41LC brass cases came in three primary lengths, although they vary quite a bit within a headstamp. The first ones were the shortest at about 0.932” to 0.937” long. In balloon-head cases, they held about 20gr of compressed black powder (BP) with a 200gr flat-bottom, heel-base, blunt-nose bullet. The next cases were about 1.130” to 1.138” long with a 200gr hollow-base, blunt-nose bullet and about 21gr of BP (also in balloon-head cases). Although the brass case lengths were far different, both cartridges were about the same overall length when loaded. The last brass case length was 1.050” to 1.100” long and was created exclusively for hand loaders so that both heel-base and hollow-base bullets could be used interchangeably (note that cartridges made from the longest brass cases and heel-base bullets are too long to fit most 41LC revolvers).

The .41 Long Colt worked surprisingly well considering the mismatch of bullet and bore sizes, but by the beginning of WWI it was in serious decline and it fell from use by the beginning of WWII. The accuracy the .41LC is adequate for what it was intended; close range self-defense, its drawback had more to do with the heavy double-action trigger pull of the Thunderer. Elmer Keith wrote in his book "Sixguns" that the "41LC was a better fight-stopper than its paper ballistics would indicate" and it was "better for self-defense than any .38 Special load made".

See also

• 10 mm caliber
• List of handgun cartridges