The M2 Carbine is the selective-fire variant of the M1 Carbine and a very significant development in the history of military rifles. It had a selector switch on the left side of the receiver, whereby a soldier could select either semi or full-automatic fire. Although it was produced too late to see extensive action during World War II, the M2 Carbine played a crucial role in the Korean War and the early stages of the Vietnam War.
Some soldiers in World War II converted their M1 Carbines to permit fully automatic firing. As a result of this, the Army’s Ordnance Department and Springfield Armory, Inland, and Winchester were ordered to develop a selective-fire version of the M1 Carbine. It was formerly accepted in late 1944 as the “Carbine Cal .30 M2.” Production began in May of 1945 at Inland and Winchester.
The M2 Carbine featured a curved 30-round magazine, and its stock was heavier at the fore-end compared to the M1 Carbine. Modification kits were also made by the government to turn M1 Carbines into M2s as part of their arsenal rebuilding and refurbishing program. It shortly became evident that a new semi-automatic personal defense weapon was necessary—something more effective than the normal side arm but smaller than a full-size battle rifle. Specifications for this new rifle included it not to weigh over five pounds, and that the effective range would be 300 yards with the new Winchester .30 carbine caliber cartridge.
In May 1941, several test models were submitted for evaluation by various firms and individual designers, one of whom was John Garand of Springfield Armory, and Eugene Reising of Harrington & Richardson. While none of the initial submissions completely met the Army’s expectations, Winchester engineers and designers moved rapidly to modify their experimental rifles to meet specifications. The resulting design, called “Carbine, Caliber .30 M1,” was adopted by the Army in a few months.
The M1 Carbine, followed by the M2, evolved into the issue to all support troops, front-line Army infantry, airborne units, and the Marine Corps in the Pacific. Although criticized for a lack of range and power in comparison with the M1 Garand rifle, the M1 Carbine was better than pistols and submachine guns at longer ranges. More than 6 million carbines were produced by 1945, making the carbine the most widely produced military arm in U.S. history.
Post-World War II, many carbines were refurbished and placed into storage. M1 and M2 carbines saw action with U.S. troops in Korea and, although officially phased out by the M14 in 1957, many continued to see action even into the early years of the Vietnam War. Several million surplus military carbines were also provided to U.S. allies throughout Asia, including the armed forces of the Philippines, South Korea, and South Vietnam.
The M2 Carbine creates many complications under the National Firearms Act. There are several methods by which a full-auto M2, or an M1 Carbine converted to M2 configuration, may be registered as a transferable machine gun: Inland M2 Carbines manufactured originally as M2s; M1 Carbine receivers converted to full auto; and registered M2 Carbine part sets. A buyer needs to know precisely what he is purchasing, as many M2 Carbines were amnesty registered in late 1968.
While not fragile, the M2 Carbine still needs attention to part functionality and overall wear due to its high rate of fire and the powerful .30 Carbine round. Without question, for its price—placing it at a lower end of the machine gun market—the M2 Carbine is an important historic firearm that reflects how personal defense weapons evolved for modern warfare.