Thompson submachine gun

Thompson Submachine Gun, Caliber .45
Thompson M1A1
Type	Submachine gun
Place of origin	United States
Service history
In service	1938–1971 (officially, U.S. military)
Used by	See Users
Wars	Irish Civil War World War II 1948 Arab–Israeli War Chinese Civil War Hukbalahap Rebellion Korean War First Indochina War Vietnam War The Troubles Bosnian War
Production history
Designer	John T. Thompson
Designed	1917–1919
Manufacturer	Auto-Ordnance Company (originally) Birmingham Small Arms Colt Savage Arms
Produced	1921–present
Number built	1,700,000 approx.
Variants	Persuader & Annihilator prototypes, M1921, M1921AC, M1921A, M1927, M1928, M1928A1, M1, M1A1
Specifications
Weight	10.8 lb (4.9 kg) empty (M1928A1) 10.6 lb (4.8 kg) empty (M1A1)
Length	33.5 in (851 mm) (M1928A1) 32 in (813 mm) (M1/A1) barrel 10.5 in (267 mm) barrel with optional Cutts Compensator 12 in (305 mm)
Cartridge	.45 ACP (11.43 × 23 mm)
Action	Blowback
Rate of fire	600-1200 rpm, depending upon model
Muzzle velocity	920 ft/s (280 m/s)
Feed system	20-round stick/box magazine 30-round stick/box magazine 50-round drum magazine 100-round drum magazine (M1 and M1A1 models do not accept drum magazines)

The Thompson submachine gun is an American submachine gun, invented by John T. Thompson in 1919 that became infamous during the Prohibition era. It was a common sight of the time, being used by both law enforcement officers and criminals.^[1] The Thompson was also known informally as: the "Tommy Gun," the "Trench Broom," the "Trench Sweeper," the "Chicago Piano," the "Chicago Typewriter," and the "Chopper."^{[2][3][4][5][6]}

The Thompson was favored by soldiers, criminals and police alike for its ergonomics, compactness, large .45 ACP cartridge, and high volume of automatic fire and among civilian collectors for its historical significance.

History and service

Development

The Thompson Submachine Gun was designed by General John T. Thompson, who was inspired by the trench warfare of World War I to develop a "one-man, hand-held machine gun", firing a pistol caliber round. While searching for a way to allow such a weapon to operate safely without the complexity of a recoil or gas operated mechanism, Thompson came across a patent issued to John Bell Blish in 1915 for a friction delayed blowback action. Thompson found a financial backer, Thomas Fortune Ryan, and started the Auto-Ordnance Corporation in 1916 for the purpose of developing his weapon. The principal designers were Theodore H. Eickhoff, Oscar V. Payne, and George E. Goll. By late 1917, the limits of the Blish lock were discovered, and it had been found that the only cartridge currently in U.S. service suitable for use with the lock was the .45 ACP (Automatic Colt Pistol). The project was then titled "Annihilator I", and by 1918, most of the design issues had been resolved. However, the war ended before prototypes could be shipped to Europe.

A Marine fires on a Japanese position using an M1 Thompson submachine gun during an advance on Okinawa in 1945.

At an Auto-Ordnance board meeting in 1919 to discuss the marketing of the "Annihilator", with the war over, the weapon was officially renamed the "Thompson Submachine Gun". While other weapons had been developed shortly prior with similar objectives in mind, the Thompson was the first weapon to be labeled and marketed as a "submachine gun".^[7] Thompson intended the weapon as an automatic 'trench-broom' to sweep enemy troops from the trenches, filling a role for which the BAR had been proven ill-suited.^[8] Contemporaneously, this concept was developed by German troops using their own Bergmann MP18 submachine guns in concert with sturmtruppen tactics.^[9]

Early use

The Thompson first entered production as the M1921. It was available to civilians, though its high price resulted in few sales. (A Thompson M1921 with one Type XX 20 shot "stick" magazine was priced at $200.00 when a Ford automobile sold for $400.00.) M1921 Thompsons were first sold in small quantities to the U.S. Post Office (to protect the mail from a spate of robberies^[10]), followed by several police departments in the United States and minor international sales to various armies and constabulary forces, chiefly in Central and South America. The U.S. Post Office also gave Thompsons to the U.S. Marine Corps in 1922 when Marines were assigned to protect against mail robberies,^[11] with the Marines putting them to use in the Banana Wars and in China.^[12] It was popular with the Marines as a point-defense weapon for countering ambush by Sandinista guerrillas and led to the organisation of 4 man fire teams with as much firepower as a 9 man rifle squad. The major complaints against the Thompson were its weight, inaccuracy at ranges over 50 yards, and its lack of penetrating power, despite the powerful round it used.^[13]

Some of the first batches of Thompsons were bought in America by agents of the illegal Irish Republic, notably Harry Boland. A total of 653 were purchased, but 495 were seized by US customs authorities in New York in June 1921. The remainder made their way to the Irish Republican Army by way of Liverpool and were used in the last month of the Irish War of Independence (1919-21). ^[14] After a truce with the British in July 1921, the IRA imported more Thompsons and they were used in the subsequent Irish Civil War (1922-23). They were not found to be very effective in Ireland however. In only 32% of actions where it was used did the Thompson cause serious casualites (death or serious injury) to those attacked. ^[15].

A lance corporal of the East Surrey Regiment, British Army equipped with a Thompson M1928 submachine gun (drum magazine), 25 November 1940

The Thompson achieved most of its early notoriety in the hands of Prohibition and Depression-era gangsters, motorized bandits and the lawmen who pursued them and in Hollywood films about their exploits, most notably in the St Valentine's Day Massacre. It was often referred to as the "gun that made the twenties roar."^[16]

In 1926, the Cutts Compensator (a recoil brake) was offered as an option for the M1921; Thompsons with the compensator were catalogued as No. 21AC, with the plain M1921 designated No. 21A.^[17]

Nationalist China also acquired a quantity for use against Japanese land forces, and eventually began producing copies of the Thompson in small quantities for use by its various armies and militias.

World War II

In 1938, the Thompson submachine gun was adopted by the U.S. military, serving during World War II and beyond.

There were two military types of Thompson SMG. The M1928A1 had provisions for box magazines and drums (the drums were disliked because of their tendency to rattle and jam). It had a Cutts compensator, cooling fins on the barrel, and its charging handle was on the top of the receiver. The M1 and M1A1 had a barrel without cooling fins, a simplified rear sight, provisions only for box magazines, and the charging handle was on the side of the receiver. Because the option to use drums was not included in the M1 and M1A1, the 30 round box magazine was designed for use with this model.

The Thompson was used in World War II in the hands of Allied troops as a weapon for scouts, non-commissioned officers, and patrol leaders. In the European theater, the gun was widely utilized in British and Canadian Commando units, as well as U.S. paratrooper and Ranger battalions who used it widely because of its high rate of fire, its stopping power and because it was very effective in close combat. A Swedish variant of the M1928A1, called Kulsprutepistol m/40 (meaning "submachine gun model 40"), served in the Swedish Army between 1940 and 1951. Through Lend-Lease, the Soviet Union also received the Thompson, but due to a shortage of appropriate ammunition in the Soviet Union, usage was not widespread.^[18]

In the Pacific Theater, Australian Army infantry and other Commonwealth forces initially used the Thompson extensively in jungle patrols and ambushes, where it was prized for its firepower, though its hefty weight of over 10 pounds and difficulties in supply eventually led to its replacement by other submachine guns such as the Owen and Austen. The U.S. Marines also used the Thompson as a limited-issue weapon, especially during their later island assaults. The Thompson was soon found to have limited effect in heavy jungle cover, where the low-velocity .45 bullet would not penetrate most small-diameter trees, or protective armor vests (in 1923, the Army had rejected the .45 Remington-Thompson, which had twice the energy of the .45ACP).^[19] In the U.S. Army, many Pacific War jungle patrols were originally equipped with Thompsons in the early phases of the New Guinea and Guadalcanal campaigns, but soon began employing the BAR in its place, especially at front (point) and rear (tail) positions, as a point defense weapon.^[20]

After World War II

By the time of the Korean War, the Thompson had seen much use by the U.S. and South Korean Military, even though Thompson will have been replaced in production by the M3 and M3A1. Many Thompsons were distributed to Chinese armed forces as military aid before the fall of Chiang Kai-Shek's government to Mao Zedong's Communist forces in 1949. During the Korean War, American troops were surprised to encounter Chinese Communist troops heavily armed with Thompsons, especially during surprise night assaults. The gun's ability to deliver large quantities of short-range automatic assault fire proved very useful in both defense and assault during the early part of the conflict. Many of these weapons were recaptured and placed back into service with American soldiers and Marines for the balance of the war.

Serb^{[citation needed]} paramilitaries during the Siege of Sarajevo. An M1A1 Thompson submachine gun is being held in the background

During the Vietnam War, some South Vietnamese army units and defense militia were armed with Thompson submachine guns, and a few of these weapons were used by reconnaissance units, advisors, and other American troops. It was later replaced by the M16. Not only did some U.S. soldiers have use of them in Vietnam, but they encountered it as well. The Vietcong liked the weapon, and used both captured models as well as manufacturing their own copies in small jungle workshops.

In the conflict in Northern Ireland, known as 'The Troubles' (1969-1998), the Thompson was again used by the Irish Republican paramilitiaries. According to historian Peter Hart, "The Thompson remained a key part of both the Official IRA and Provisional IRA arsenals until well into the 1970s when it was superseded by the Armalite and the AK-47" ^[21]

The Thompson was also used by U.S. and overseas law enforcement and police forces, most prominently by the FBI. The FBI used Thompsons until 1976, when it was declared obsolete. All Thompsons in U.S. government possession were destroyed, except for a few token museum pieces and training models.

The Thompson, or copies of the gun, are still seen from time to time in modern day conflicts, such as the Bosnian War.

Operating characteristics

Early versions of the Thompson had a fairly high rate of fire, approaching 800-850 rounds per minute. Later M1 and M1A1 Thompsons averaged 600 rpm.^[22] This rate of fire, combined with a rather heavy trigger pull and a stock with excessive drop, increases the tendency of the gun to climb off target in automatic fire.^[22][23] Compared to modern 9mm submachine guns, the .45 Thompson is quite heavy. This was one of the major complaints against the weapon made by servicemembers of militaries that issued the Thompson.^[13]

Although the magazine provided significant firepower, in military service it was found to be overly heavy and bulky, especially when slung on patrol or on the march.^[23] For this reason, the 20-round and later 30-round box magazines soon proved most popular with military users, and drum compatibility was eliminated from the wartime M1 and M1A1 models. The Thompson was one of the earliest submachine guns to incorporate a double-column, double-feed box magazine design, which undoubtedly contributed to the gun's reputation for reliability. In addition, the gun performed better than most after exposure to rain, dirt, and mud.^[13]

Because of its gangster-era and World War II connections, Thompsons are highly sought as collector's items. An original Model 1928 in working condition can easily fetch US$20,000 or more. Approximately 1,700,000 of these weapons were produced by Auto-Ordnance, Savage Arms, and Colt, with 1,387,134 being the simplified World War II M1 and M1A1 variants (without the Blish lock and oiling system^[24]). Semi-automatic versions configured as civilian-legal rifles are currently produced by Auto-Ordnance Company, a division of Kahr Arms, for the collector market at prices ($900.00 to $1400.00) considerably lower than the prices for originals.

Variants

Persuader and Annihilator

There were two main experimental models of the Thompson. The Persuader was a belt-fed version developed in 1918, and the Annihilator was fed from a 20 or 30-round box magazine, which was an improved model developed in 1918 and 1919. Additionally, the 50- and 100-round drum magazines were developed.

Model of 1919

The Model of 1919 was limited to about 40 units, with many variations noted throughout. The weapons had very high cyclic rates around 1,500 rpm.^[25] This was the weapon Brigadier General Thompson demonstrated at Camp Perry in 1920. Almost all Model of 1919s were made without buttstocks and front sights, and the final version closely resembled the later Model of 1921. The New York City Police Department was the largest purchaser of the Model of 1919. This model was designed as an automatic Colt .45 to "sweep" trenches with bullets. Some experimental calibers were .45ACP (11.4x23mm), .22LR, .32 ACP, .38 ACP, and 9mmP.^[26]

Model of 1921

The "Anti-Bandit Gun": 1920s Advertisment of the Thompson M1921 for United States law enforcement forces

The Model of 1921 was the first major production model. Fifteen thousand were produced by Colt for Auto-Ordnance. In its original design, it was finished more like a sporting weapon, with a blued, finned barrel and vertical foregrip and the Blish lock. The Model of 1921 was quite expensive to manufacture, with the original retail cost around $225, because of its high quality wood furniture and finely-machined parts. The Model of 1921 was famous throughout its career with police and criminals and in motion pictures. The weapon had a relatively high 800+ rpm^{[citation needed]} rate of fire.

Thompson Autorifle and SMG Model of 21

Model of 1923

The Model of 1923 was introduced to potentially expand the Auto-Ordnance product line and was demonstrated for the U.S. Army. It fired the more powerful .45 Remington-Thompson cartridge from a 14-inch (35.5 cm) barrel, with greater range than the .45 ACP. It introduced a horizontal forearm, sling, bipod and bayonet lug. The M1923 was intended to fill the same role of the M1918 Browning Automatic Rifle (BAR) which the Army was already satisfied with, and did not give the Model of 1923 much consideration, so it was not adopted.

BSA Thompsons

In an attempt to expand interest and sales overseas, Auto-Ordnance partnered with and licensed Birmingham Small Arms Company (BSA) in England to produce a European model. These were produced in small quantities and have a different appearance than the classic style. The BSA 1926 was manufactured in 9 mm and 7.63 Mauser calibre and were tested by various governments, including France in the mid 1920s. It was never adopted by any military force, and only a small number were produced.^[27]

Model of 1927

The Model of 1927 was the open bolt semi-automatic-only version of the M1921. It was made by modifying an existing Model of 1921, including replacing certain parts. The "Thompson Submachine Gun" inscription was machined over to replace it with "Thompson Semi-Automatic Carbine", and the "Model of 1921" inscription was also machined over to replace it with "Model of 1927." Although the Model of 1927 was semi-automatic only, it was easily converted to fully automatic by utilizing a Model of 1921 receiver, and is classified as a machine gun under the National Firearms Act of 1934 by a 1982 BATF ruling making all open bolt semi automatic firearms classified as machineguns.

Model of 1928

The Model of 1928 was the first type widely used by military forces, with the U.S. Navy and U.S. Marine Corps as major buyers through the 1930s. The original Model of 1928s were Model of 1921s with weight added to the actuator, which slowed down the cyclic rate of fire, a U.S. Navy requirement. The Navy Model of 1928 has several names by collectors today they are; the 'Colt Overstamp', 'The 1921 Overstamp', '28 Navy', or just '28N'. The "overstamp" term refers to the '1' in '1921' being stamped over with an '8'. The 1928 Thompson would be the last small arm adopted by the U.S. Army that used a year designation in the official nomenclature. With the start of World War II, major contracts from several countries saved the manufacturer from bankruptcy.

M1928A1

Thompson M1928A1, field stripped

M1928A1 at Fort Knox, Kentucky, June 1942

The M1928A1 variant entered mass production before the attack on Pearl Harbor, as on-hand stocks ran out. Changes included a horizontal forend, in place of the distinctive vertical foregrip ("pistol grip"), and a provision for a military sling. Despite new U.S. contracts for Lend-Lease shipments abroad to China, France, and the United Kingdom, as well as the needs of American armed forces, only two factories supplied M1928A1 Thompsons during the early years of World War II. Though it could use both the 50-round drum and the 20- or 30-round box magazines, active service showed the drums were more prone to jamming, rattled when moving, and were too heavy and bulky on long patrols. 562,511 were made. Wartime production variants had a fixed rear sight without the triangular sight guard wings and a non-ribbed barrel both like that found on the M1/M1A1.

In addition, the Soviet Union received M1928A1s, included as standard equipment with the M3 light tanks obtained through Lend-Lease. The weapons were never issued to the Red Army, however, because of a lack of .45 ACP ammunition on the Eastern Front, and were simply put in storage. As of September 2006, limited numbers of these weapons have been re-imported from Russia to the United States as disassembled "spare parts kits", the entire weapon less the receiver (as required by Federal law).

M1

Fire Controls M1 Thompson Front lever is selector switch set for full auto.

Answering the call for further simplification, the M1 was standardized in April 1942 as the United States Submachine Gun, Cal. .45, M1. Rate of fire was reduced to approximately 600-700 rpm. First issued in 1943, the M1 utilized a simple blowback operation, the charging handle was moved to the side, and the flip-up adjustable rear sight replaced with a fixed aperture (peep sight). Wartime production variants omitted the triangular rear sight guard wings. The slots adjoining the magazine well allowing use of the drum magazine were removed. The less expensive and more-easily manufactured "stick" magazines were used exclusively in the M1, with a new 30-round version joining the familiar 20-round type. The Cutts compensator, barrel cooling fins, and Blish lock were omitted while the buttstock was permanently affixed.

M1A1

Both sides of the Thompson M1A1

The M1A1, formally adopted as the United States Submachine Gun, Cal. .45, M1A1, could be produced in half the time of the M1928A1, and at a much lower cost. The multi-piece firing pin of the M1 was supplanted by a simplified firing pin machined into the face of the bolt. The 30-round magazine became more common. In 1939, Thompsons cost the government $209 apiece. By the spring of 1942, cost reduction design changes had brought this down to $70. In February 1944, the M1A1 reached a low price of $45 each, including accessories and spare parts. By the end of the Vietnam War, the M1A1 was replaced with the even lower-cost M3 (commonly called "Grease Gun").

Model 1927A1

The Model 1927A1 is a semi-automatic only version of the Thompson, originally produced by Auto-Ordnance (West Hurley, New York) for the civilian gun market from 1974 to 1999. It is officially known as the "Thompson Semi-Automatic Carbine, Model of 1927A1." The internal design is completely different and operates from the closed bolt, hence is legal for civilian ownership in the United States without a special license. It has been produced since 1999 by Kahr Arms of Worcester, Massachusetts. This weapon should not be confused with the earlier Model of 1927 produced by Colt for Auto-Ordnance, although its name and designation refers to the earlier semi-automatic model. The Model 1927A1 is the semi-automatic replica of the Thompson Models of 1921 and 1928; the Auto-Ordnance replica of the Thompson M1 and M1A1 is known as the TM1 and may be found marked "Thompson Semi-Automatic Carbine, Caliber .45M1".

Model 1927A3

The Model 1927A3 is a semi-automatic, .22 caliber version of the Thompson produced by Auto-Ordnance in West Hurley.

Model 1927A5

Firing the 1921 Thompson

The Model 1927A5 is a semi-automatic pistol version, .45ACP version of the Thompson originally produced by Auto-Ordnance in West Hurley. It featured an aluminum receiver to reduce weight. It has been produced since 2008 by Kahr Arms of Worcester, Massachusetts as the "M1927A1 TA5".

Civilian ownership

United States

Because of the perceived popularity of submachine guns such as the Thompson with gangsters in the 1920s and 1930s, the United States Congress passed the National Firearms Act in 1934. Among its provisions, all owners of any fully-automatic firearm were required to register them with the predecessor agency of the modern Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). The law also placed severe restrictions on the possession, transfer and transport of the weapons.

There are several U.S. made automatic and semi-automatic variants. These are less regulated at the federal level but are still banned in some states because of their resemblance to the fully-automatic version.

Canada

Thompson submachine guns (including all variants or modified versions) are classified as Prohibited Weapons in Canada. Consequently, they cannot be legally imported or owned except under very limited circumstances.^[28][29]

Users

•  Australia^[30]
•  Canada^[31]
•  China: Limited, sometimes unlicensed copies.^[32][33]
•  France^[32]
•  North Vietnam: Limited, sometimes unlicensed copies.^[32]
•  Ireland: The IRA used the 1921 variant, mainly during the early 60s to 70s.^[34]
•  Philippines: Used by Philippine Scouts.
•  Soviet Union^[35]
•  United Kingdom^[36]
•  United States^[35]

References

Notes

Bibliography

External links

Wikimedia Commons has media related to: M1 Thompson

• Auto Ordnance
• M1923 Thompson Gun at the Royal Danish Arsenal Museum
• Modern Firearms article
• Philip Sharpe article
• Colt Thompson Cyber Museum
• The Unofficial Tommy Gun Home Page
• Thompson Collectors Association