The M1 Carbine is a lightweight semi-automatic rifle that was a standard firearm in the US military during World War II and the Korean War.
The weapon was designed in response to the blitzkrieg tactical doctrine of the Axis, where Nazi troops would quickly and deeply penetrate Allied front lines. Facing an enemy that used this tactical approach meant that support troops came under direct attack by front line forces. In anticipation for this possibility, this carbine was commissioned to supply an adequate defensive weapon to those troops.
In response to a competitive design process, the Winchester firearms company submitted a design developed mostly by David M. "Carbine" Williams, a some-time bootlegger who came up with a significant part of the design while serving a prison sentence for murder. Upon his release, Williams went to work for Winchester and helped complete the design.
Although the M1 Carbine is often described as a development of the M1 Garand rifle, it is not. It has a different internal design, based upon a lightweight tappet and slide gas system and interchangeable magazines. It fires a smaller and lighter 0.30 inch caliber cartridge which is very different, in both design and performance, from the full-sized .30 inch cartridge used in the Garand.
Eventually, the weapon was also issued to some regular troops, particularly officers, sergeants, and radio operators, since it was less unwieldy than the M1 Garand rifle, and was still considered suitable for close quarters combat. A folding stock version, the M1A1, was issued to paratroopers. Late in the Korean War, a fully automatic version, the M2, was introduced. An M3 version, which incorporated a mount for a primitive active infrared night vision sight, was also made.
Reaction to the M1 Carbine by the troops who used it was mixed. While many appreciated the light weight and superior ergonomics of the weapon, others derided it and its cartridge as having inadequate lethality against the enemy. The truth is somewhere in between. Early versions of the Carbine had poor sights, and when fired, the .30 inch caliber US Carbine cartridge loses considerable lethality after 150 yards. However, with improved sights and used within the limitations of its ammunition, the Carbine became a much more formidable weapon.
6.25 million M1 Carbines of various models were manufactured, thus making it the most produced small arm in American military history. Despite being designed by Winchester, the great majority of these were made by other companies. The largest producer was the Inland division of General Motors, but many others were made by contractors as diverse as IBM and the Rock-Ola jukebox company.
After the Korean War the Carbine was widely exported to US allies and client states, and was used as a front-line weapon well into the Vietnam era. Surplus Carbines are popular among firearms enthusiasts in the US and elsewhere. Limited civilian production of the design, by Iver Johnson and other companies, extended into the 1990s.
The M1 Carbine is still in use, even today, by enthusiasts and police. The inherent accuracy and limited penetration of the .30 Carbine round has been found to be an advantage in some urban policing scenarios.