M1 carbine
The M1 Carbine is a lightweight semi-automatic carbine chambered in the.30 carbine cartridge that was issued to the U.S. military during World War II, the Korean War, and the Vietnam War. The M1 Carbine was produced in several variants and was widely used by military, paramilitary, and police forces around the world after World War II, most notably by the armed forces of South Korea and South Vietnam.
The M2 Carbine is the selective-fire version of the M1 Carbine, capable of firing in both semi-automatic and full-automatic. The M3 Carbine was an M2 Carbine with an active infrared scope system.
Despite having a similar name and physical outward appearance, the M1 Carbine is not a carbine version of the M1 Garand rifle. On 1 July 1925, the U.S. Army began using the current naming convention where the "M" is the designation for "Model" and the number represents the sequential development of equipment and weapons. Therefore, the "M1 Carbine" was the first carbine developed under this system. The "M2 Carbine" was the second carbine developed under the system, etc.
Development history
Limitations of weapons in the U.S. arsenal
Prior to World War II, the U.S. Army Ordnance Department received reports that the full-size M1 rifle was too heavy and cumbersome for most support troops to carry. During pre-war and early war field exercises, it was found that the M1 Garand impeded these soldiers' mobility, as a slung rifle would frequently catch on brush or hit the back of the helmet and tilt it over the eyes. Many soldiers found the rifle slid off the shoulder unless slung diagonally across the back, where it prevented the wearing of standard field packs and haversacks.Additionally, Germany's use of glider-borne and paratrooper forces to launch surprise blitzkrieg attacks behind the front lines generated a request for a new compact infantry weapon to equip support troops. This request called for a compact, lightweight defensive weapon with greater range, accuracy and firepower than a handgun, while weighing half as much as the Thompson submachine gun or the M1 rifle. The U.S. Army decided that a carbine-type weapon would adequately fulfill all of these requirements, and specified that the new arm should weigh no more than and have an effective range of. Paratroopers were also added to the list of intended users and a folding-stock version would also be developed.
Design
In 1938, the chief of infantry requested that the ordnance department develop a "light rifle" or carbine, though the formal requirement for the weapon type was not approved until 1940.Winchester developed the.30 Carbine cartridge for the ordnance department. Winchester at first did not submit a carbine design, as it was occupied in developing the Winchester G30 rifle. The G30 rifle originated as a design by Jonathan "Ed" Browning, half-brother of the famous firearm designer John Moses Browning. A couple of months after Ed Browning's death in May 1939, Winchester hired David Marshall "Carbine" Williams who had begun work on a short-stroke gas piston design while serving a prison sentence at a North Carolina minimum-security work farm. Winchester, after Williams' release, had hired Williams on the strength of recommendations of firearms industry leaders and hoped Williams would be able to complete various designs left unfinished by Ed Browning, including the Winchester G30 rifle. Williams incorporated his short-stroke piston in the existing design as the G30M. After the Marine Corps' semi-automatic rifle trials in 1940, Browning's rear-locking tilting bolt design proved unreliable in sandy conditions. As a result, Williams redesigned the G30M to incorporate a Garand-style rotating bolt and operating slide, retaining the short-stroke piston as the.30 M2 Winchester Military Rifle. By May 1941, Williams had shaved the M2 rifle prototype from about to a.
Ordnance found unsatisfactory the first series of prototype carbines submitted by several firearms companies and some independent designers. Winchester had contacted the ordnance department to examine their rifle M2 design. Major René Studler of ordnance believed the rifle design could be scaled down to a carbine which would weigh and demanded a prototype as soon as possible. The first model was developed at Winchester in 13 days by William C. Roemer, Fred Humeston and three other Winchester engineers under the supervision of Edwin Pugsley and was essentially Williams' last version of the.30-06 M2 scaled down to the.30 SL cartridge. This patchwork prototype was cobbled together using the trigger housing and lockwork of a Winchester M1905 rifle and a modified Garand operating rod. The prototype was an immediate hit with army observers.
After the initial Army testing in August 1941, the Winchester design team set out to develop a more refined version. Williams participated in the finishing of this prototype. The second prototype competed successfully against all remaining carbine candidates in September 1941, and Winchester was notified of their success the next month. Standardization as the M1 carbine was approved on 22 October 1941. This story was the loose basis for the 1952 movie Carbine Williams starring James Stewart. Contrary to the movie, Williams had little to do with the carbine's development, with the exception of his short-stroke gas piston design. Williams worked on his own design apart from the other Winchester staff, but it was not ready for testing until December 1941, two months after the Winchester M1 carbine had been adopted and type-classified. Winchester supervisor Edwin Pugsley conceded that Williams' final design was "an advance on the one that was accepted" but noted that Williams' decision to go it alone was a distinct impediment to the project, and Williams' additional design features were not incorporated into M1 production. In a 1951 memo written in fear of a patent infringement lawsuit by Williams, Winchester noted his patent for the short-stroke piston may have been improperly granted as a previous patent covering the same principle of operation was overlooked by the patent office.
In 1973, the senior technical editor at the NRA contacted Edwin Pugsley for "a technical last testament" on M1 Carbine history shortly before his death on 19 November 1975. According to Pugsley, "The carbine was invented by no single man," but was the result of a team effort including: William C. Roemer, David Marshall Williams, Fred Humeston, Cliff Warner, at least three other Winchester engineers, and Pugsley himself. Ideas were taken and modified from the Winchester M2 Browning rifle, the Winchester Model 1905 rifle, M1 Garand, and a percussion shotgun in Pugsley's collection.
Features
Ammunition
The.30 Carbine cartridge is essentially a rimless version of the obsolete.32 Winchester Self-Loading cartridge introduced for the Winchester Model 1905 rifle. The propellant was much newer, though, taking advantage of chemistry advances. As a result, the.30 Carbine cartridge is approximately 27% more powerful than its parent cartridge. A standard.30 Carbine ball bullet weighs 110 grains, a complete loaded round weighs 195 grains and has a muzzle velocity of giving it 967 ft·lbf of energy, when fired from the M1 carbine's barrel.In comparison, the.30-06 Springfield ball round used by the M1 Garand is almost three times as powerful as the.30 Carbine, while the carbine round is twice as powerful as the.45 ACP-caliber Thompson submachine gun in common use at the time. As a result, the carbine offers much better range, accuracy and penetration than those submachine guns. The M1 carbine is also half the weight of the Thompson and fires a lighter cartridge. Therefore, soldiers armed with the carbine can carry much more ammunition than those armed with a Thompson.
Categorizing the M1 Carbine series has been the subject of much debate. Although commonly compared to the later German StG 44 and Russian AK-47, the M1 and M2 Carbines are under-powered and outclassed. Instead, the carbine falls somewhere between the submachine gun and assault rifle and could be called a precursor of the personal defense weapon since it fulfilled a similar role.
One characteristic of.30 caliber Carbine ammunition is that from the beginning of production, non-corrosive primers were specified. This was the first major use of this type of primer in a military firearm. Because the rifle had a closed gas system, not normally disassembled in the field, corrosive primers would have led to a rapid deterioration of the function of the gas system. The use of non-corrosive primers was a novelty in service ammunition at this time. Some failures to fire were reported in early lots of.30 caliber Carbine ammunition, attributed to moisture ingress of the non-corrosive primer compound.
Sights, range and accuracy
The M1 Carbine entered service with a simple flip sight, which had two settings:. However, field reports indicated that this sight was inadequate, and in 1944, it was replaced by a sliding ramp-type adjustable sight with four settings:,,, and. This new rear sight was also adjustable for windage.At, the M1 Carbine can deliver groups between, sufficient for its intended purpose as a close-range defensive weapon. The M1 carbine has a maximum effective range of ; while the practical effective range is about. According to Frank C. Barnes, effective range is limited to for sporting purposes.
Magazines
The M1 Carbine entered service with a standard straight 15-round box magazine. The introduction of the select-fire M2 Carbine in October 1944 also brought into service the curved 30-round box magazine or "Banana Mag". After WWII, the 30-round magazine quickly became the standard magazine for both the M1 and M2 carbines, although the 15-round magazine remained in service until the end of the Vietnam War.Perhaps the most common accessory used on the M1 carbine was a standard magazine belt pouch that was slid over the stock and held two extra 15-round magazines. This field adaptation was never officially approved but proved an efficient method to supply extra ammunition in combat. After the introduction of the 30-round magazine, it was common for troops to tape two 30-round magazines together, a practice that became known as "jungle style". This led the military to introduce the "Holder, Magazine T3-A1" also called the "jungle clip", a metal clamp that held two magazines together without the need for tape.
The 30-round magazines introduced for use with the selective-fire M2 Carbine would not be reliably retained by the magazine catch made for the original M1 carbine which was designed to retain a 15-round magazine, so the much heavier 30-round magazine would not be properly seated in the M1 carbine magazine well. The loaded 30-round magazine would typically slant or even fall out, which contributed to the poor reliability record of the 30-round magazines. Because of their thin steel construction, they were also more prone to damage due to their added length and weight when loaded. In response to these issues, early production M1 Carbines had to be fitted with the type IV magazine catch used on the M2 carbine if they were to be used with 30-round magazines in order to ensure reliable loading and feeding. The type IV magazine catch has a leg on the left side to correspond with the additional nub on the 30-round magazines.
Initial combat reports noted that the M1 Carbine's magazine release button was often mistaken for the safety button while under fire. When this occurred, pressing the magazine release caused the loaded magazine to drop, while the safety remained in the off position. As a result, the push-button safety was redesigned using a rotating lever.