.44 Colt

.44 Colt
Benet primed .44 Colt & Remington, .44 Colt and .44 Remington.
Type	Revolver
Place of origin	US
Service history
In service	1871-1873
Used by	United States Army
Production history
Produced	1871?-1940?
Specifications
Bullet diameter	.451 in (11.5 mm)
Base diameter	.456 in (11.6 mm)
Rim diameter	.483 in (12.3 mm)
Case length	1.10 in (28 mm)
Overall length	1.50 in (38 mm)
Rifling twist	1:16
Primer type	large rifle
Ballistic performance
Bullet mass/type Velocity Energy 225 gr (15 g) (U.S. Army black powder load) 640 ft/s (200 m/s) 207 ft·lbf (281 J) 225 gr (15 g) 640 ft/s (200 m/s) 207 ft·lbf (281 J) 210 gr (14 g) (factory load) 660 ft/s (200 m/s) 206 ft·lbf (279 J) 210 gr (14 g) (original factory black powder load) 660 ft/s (200 m/s) 206 ft·lbf (279 J) 210 gr (14 g) (smokeless, Lyman #429185) 650 ft/s (200 m/s) 197 ft·lbf (267 J)
Source(s): Barnes & Amber 1972

The .44 Colt was an American centerfire revolver cartridge produced commercially from 1871 until the 1940s.

The cartridge was developed for the United States Army, and introduced by Colt's Patent Firearms around 1871. The Army used it until 1873, at which time it was replaced by the better known .45 Colt cartridge used in the recently adopted Colt Single Action Army revolver.

The .44 Colt was used in the Richards-Mason conversions of Colt's 1860 Army percussion revolver. The conversion process involved boring through the chambers of the obsolete cap and ball revolvers to enable them to chamber centerfire metallic cartridges.

This process left a chamber of uniform diameter, with no step at the front. Thus the bullet and the brass case were made the same diameter, with a short "heel" section at the base of the bullet of smaller diameter inserted in the mouth of the case.

Modern .44 Colt ammunition is dimensionally similar to .44 Special with regard to bullet diameter and case width, the main exceptions being the shorter case length and smaller rim diameter.

The original .44 Colt loading used a heeled, outside lubricated bullet. The major diameter of the bullet was approximately the groove diameter (.451") of the converted ".44" cap and ball revolver. The smaller "heel" at the base of the bullet was sized to fit inside the brass case at approximately .430".

Upon firing, the ductile soft lead bullet (alloys of pure to nearly pure lead were used) allowed the base of the bullet to "bump up" to first the chamber diameter in the cylinder, then jump the gap, through the forcing cone into the rifling. This is effective with black powder, but less so with smokeless powder. Alloying the lead with tin or antimony to harden it makes this nearly impossible. Use of hard alloys typically leads to poor accuracy.