Editing Thompson submachine gun (section)

==Variants==
===Prototypes===
====Persuader and Annihilator====
There were two main experimental models of the Thompson. The ''Persuader'' was a [[Belt (firearm)|belt-fed]] version developed in 1917/18. It was partially built, but never completely finished. The ''Annihilator'', serial no. Ver 10 prototypes were similar in appearance to the later models, but without the rear sight and butt stock mounts. The Annihilator prototypes in which box magazine adapters were present, were first were fed from a 20-round box magazine, but later, the 50- and 100-round [[drum magazine]] models were developed.

====Model 1919====
Starting with the Serial no. 11, the Model 1919 takes the final appearance of the later Thompsons with the rear sights and butt stock. The Model 1919 was limited to about 40 units; the first built did not use the drums, as it was too difficult to fire. Many variations have been noted within this model. The weapons had very high cyclic rates up to 1,500&nbsp;rpm.{{sfn|Bearse|1994|p=210}} This was the weapon Brigadier General Thompson demonstrated at [[Camp Perry]] in 1920. A number of Model 1919s were made without butt stocks, rear and front sights, but the final version closely resembled the later Model 1921. This model was designed to "sweep" trenches with bullets. The [[New York City Police Department]] was the largest purchaser of the M1919. Some experimental calibers aside from the standard [[.45 ACP]] (11.4x23mm) were the [[.22LR]], [[.32 ACP]], [[.38 ACP]], and [[9mm Luger|9mm]].<ref name="Fitz2487"/>

====.351 WSL variant====
Only one prototype was made in [[.351 WSL]] using a standard 20" barrel which had a ROF of 1000rpm. 1926 it was shipped to [[France]] for testing but the [[Extractor (firearms)|extractor]] broke after 10 rounds, no spare parts were delivered.<ref>{{Cite web |date=2019-10-19 |title=Colt Thompsons in French Service |url=http://www.smallarmsreview.com/display.article.cfm?idarticles=1599 |access-date=2024-02-09 |archive-url=https://web.archive.org/web/20191019054958/http://www.smallarmsreview.com/display.article.cfm?idarticles=1599 |archive-date=2019-10-19 }}</ref><ref>{{Cite web |date=2022-11-29 |title=Loads for an Auto Ordnance Thompson Carbine {{!}} Load Data Article |url=https://loaddata.com/Article/BenchTopics/Loads-for-an-Auto-Ordnance-Thompson-Carbine/463 |access-date=2024-02-09 |archive-url=https://web.archive.org/web/20221129143306/https://loaddata.com/Article/BenchTopics/Loads-for-an-Auto-Ordnance-Thompson-Carbine/463 |archive-date=2022-11-29 }}</ref>

====Thompson .30 Carbine====
{{Main articles|Thompson Light Rifle}}
The layout and ergonomics of the Thompson submachine gun were also considered for the role of a Light Rifle before the adoption of the [[M1 Carbine]]. An example known as the "Calibre .30 Short Rifle" was based on the M1921/27 variants.<ref>The Ultimate Thompson Book by Tracie L. Hill</ref> However, it was turned down without testing due to logistical problems.<ref>{{cite web|url=http://www.thefirearmblog.com/blog/2016/10/20/thompson-tommy-gun-smg-30-carbine-version/|title=Thompson "Tommy Gun" SMG... .30 Carbine Version -|date=20 October 2016}}</ref>

====.30-06 variant====
A .30–06 variant was intended as a rival to the M1918 BAR. It had an extended receiver with a recoil buffer and was fed from 20-round magazines.<ref>{{cite web|url=https://patents.google.com/patent/US1397698A/en|title=Gun}}</ref>

==== M1944 Hyde Carbine ====
{{Main articles|M1944 Hyde Carbine}}
[[.30 Carbine]] Variant.

===Production===
====Model 1921====
[[File:Thompson 1921 submachine gun.jpg|thumb|Thompson Model 1921.]]
The Model 1921 (M1921) 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 an adjustable rear sight, a blued, finned barrel and vertical [[foregrip]] (or pistol grip) and the Blish lock. The M1921 was quite expensive to manufacture, with the original retail price around $200, because of its high-quality wood furniture and finely [[machined]] parts. The M1921 was famous throughout its career with police and criminals and in motion pictures. This model gained fame from its use by criminals during Prohibition, and was nicknamed "Tommy gun" by the media.<ref>{{cite news |last1=Johnson |first1=Cara |title='The Gun That Made The '20s Roar': Inside The Blood-Soaked History Of The Infamous Tommy Gun |url=https://allthatsinteresting.com/tommy-gun |access-date=5 July 2022 |work=All That's Interesting |date=27 June 2022}}</ref>

====Model 1923====
The Model 1923 was a heavy submachine gun 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 (firearms)|cartridge]] which fired a heavier {{convert|250|gr|oz g|abbr=on|lk=on}} bullet at muzzle velocities of about {{convert|1,450|ft/s|m/s|abbr=on}} and energy about {{convert|1170|ftlb|J|abbr=on|lk=on}}, with greater range than the .45 ACP. It introduced a horizontal [[Forearm (firearm component)|forearm]], improved inline stock for accuracy, {{convert|14|in|cm|abbr=on}} barrel, [[bipod]], and [[bayonet]] lug. The M1923 was intended to rival the [[M1918 Browning Automatic Rifle]] (BAR), with which the Army was already satisfied. The Army did not give the Model 1923 much consideration, so it was not adopted. In addition to the .45 Remington–Thompson, the M1923 Thompsons were to be made available to prospective buyers in several calibers, including [[.45 ACP]], [[9mm Parabellum]], [[9mm Mauser]], and [[.351 Winchester]] Self-loading.<ref>Small Arms Review, Vol. 26, No. 5, p. 35</ref>

====Model 1921AC (1926)====
While not a new model in the usual sense of incorporating major changes, in 1926 the Cutts Compensator (a [[muzzle brake]]) was offered as an option for the M1921; Thompsons with the compensator were cataloged as No. 21AC at the original price of $200.00, with the plain M1921 designated No. 21A at a reduced price of $175.00.<ref name="Frank Iannamico 1928"/> The Model 1921 was thereafter referred to as Model 1921A or Model 1921AC, though some collectors still refer to it as the Model 1921.

====Model 1928====
[[File:Thompson submachine gun at Alcatraz.jpg|thumb|left|A deactivated M1928 Thompson submachine gun at Alcatraz, San Francisco Bay.]]

The Model 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 1928s were Model 1921s with weight added to the actuator, which slowed down the [[cyclic rate]] of fire, a United States Navy requirement. On these guns, the model number "1921" on the receiver was updated by stamping an "8" over the last "1". The Navy Model 1928 has several names among collectors: the "Colt Overstamp", "1921 Overstamp", "28 Navy", or just "28N".

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]]. A notable variant of the Model 1928 with an aluminum receiver and tenite grip, buttstock, and forend, was made by Savage.<ref>{{cite web |url=http://www.machinegunbooks.com/eleven.html |title=Thompson Gallery |publisher=www.MachineGunBooks.com |access-date=2011-12-25 |archive-date=2013-01-04 |archive-url=https://web.archive.org/web/20130104121826/http://www.machinegunbooks.com/eleven.html |url-status=dead }}</ref>

====M1928A1====
[[File:Halftrack-fort-knox-4.jpg|thumb|M1928A1 at [[Fort Knox, Kentucky|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 (firearms)|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 favored the box magazines as 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 those found on the M1/M1A1.

In addition, the Soviet Union received M1928A1s, included as standard equipment with the [[M3 Stuart|M3]] [[light tank]]s obtained through Lend-Lease. These submachine guns were used to a limited extent by the Red Army.<ref>{{cite web|url=https://pamyat-naroda.ru/documents/view/?id=238922686|title = Память народа::Поиск документов частей}}</ref>

Some M1928A1 Thompsons were used by the French before and during the Battle of France (1940) under the designation "Pistolet-mitrailleur 11 mm 43 (C.45) M. 28 A1."

An M1928A1 with an unusual inline stock, modified with elevated sights to increase accuracy, also was produced. Some Thompsons were built with a folding stock, similar to [[M1A1 Carbine]]s used by Allied tank crews, drivers and paratroopers and submarine raiders.<ref>{{cite web|url=http://www.forgottenweapons.com/experimental-thompson-stock/|title=Experimental Thompson Stock|work=Forgotten Weapons|date=2012-12-07}}</ref>

===Service variants===
{{more citations needed section|date=February 2016}}

====Thompson Machine Carbine (TMC)====
In 1940, Commonwealth troops in Egypt and North Africa were issued commercial model Lend-Lease Colt- and Savage-manufactured M1928s. Section leaders carried them instead of pistols or rifles. Many of the Colt models had French-language manuals packed with them as they had been abruptly diverted to England after the fall of France. They soon discovered that the weapon was prone to jamming due to sand. To fix this, the armorers removed the Blish Lock and replaced it with a hex bolt to keep the cocking handle and bolt together. The 20-round Type XX magazines had their peep-holes welded shut to keep sand out and the 50-round Type L drums were discontinued. Ammunition was scarce as it was either in small lots of Lend-Lease commercial ammo or obtained from adjacent American troops. It was later replaced by the [[9mm Parabellum|9mm]] [[Sten gun]] and [[Lanchester SMG]].

Models used in the Pacific by Australian troops had their sling swivels remounted on the left side to allow it to be fired more easily while prone. A metal sling mount was fitted to the left side of the wooden buttstock. Ammunition was manufactured in Australia or obtained from adjacent American troops. It was later replaced by the [[Owen Gun|Owen Machine Carbine]].

====M1====
[[File:Thompson submachine gun Firecontrols.jpg|thumb|Fire controls on an M1 Thompson. Front lever is the selector switch, set for semi-automatic fire.]]

Responding to a request 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&nbsp;rpm.

First issued in 1943, the M1 uses a simple [[Blowback (arms)|blowback]] operation, with the charging handle moved to the side. The flip-up adjustable Lyman rear sight was replaced with a fixed L sight. Late M1s had triangular guard wings added to the rear L sight, which were standardized on the M1A1. The slots adjoining the magazine well allowing the use of a drum magazine were removed. A new magazine catch with the provision for retaining drum magazines removed, was produced, but most M1s and later M1A1s retained the original. 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 [[Stock (firearms)|buttstock]] was permanently affixed. Late production M1 stocks were fitted with reinforcing bolts and washers to prevent splitting of the stock where it attached to the receiver. The British had used improvised bolts or wood screws to reinforce M1928 stocks. The M1 reinforcing bolt and washer were carried over to the M1A1 and retrofitted to many of the M1928A1s in American and British service. Late M1s also had simplified fire control switches, also carried over to the M1A1. Certain M1s had issues with high rate of fire climbing up to ~800 RPM. The exact cause remains unknown, but was resolved with the transition to the M1A1.<ref>[https://smallarmsreview.com/display.article.cfm?idarticles=2163 M1 Vs M1A1 Thompson Submachine Gun Cyclic rate]</ref>

====M1A1==== <!-- [[M1A1]] links here -->
[[File:ThompsonM1A1VWM.jpg|thumb|right|The M1A1 Thompson submachine gun on display at the Virginia War Museum.]]

The M1A1, standardized in October 1942 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 main difference between the M1 and M1A1 was the bolt. The M1 bolt had a floating firing pin and hammer, and the bolt of the M1A1 had the firing pin machined to the face of the bolt, eliminating unnecessary parts. The reinforced stock and protective sight wings were standard. 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, although the difference in price between the M1 and M1A1 was only $0.06. By the end of the war, the M1A1 was replaced with the even lower-cost M3 (commonly called the "Grease Gun").

===Semi-automatic===
====Model 1927====
The Model 1927 was the open bolt semi-automatic version of the M1921. It was made by modifying an existing Model 1921, including replacing certain parts. The "Thompson Submachine Gun" inscription was machined over to replace it with "Thompson Semi-Automatic Carbine", and the "Model 1921" inscription was also machined over to replace it with "Model 1927." Although the Model 1927 was semi-automatic only, it was easily converted to fully automatic by installing a full-auto Model 1921 fire control group (internal parts). Most Model 1927s owned by police have been converted back to full-auto.{{sfn|Iannamico|2000|p=21}} The original Model 1927 is classified as a machine gun under the [[National Firearms Act]] of 1934 (a) by being "readily convertible" by swapping parts and (b) by a [[Open bolt#Legality|1982 BATF ruling]] making all open bolt semi-automatic firearms manufactured after the date of this ruling classified as machine guns.

====Model 1927A1====
The Model 1927A1 is a semi-automatic replica version of the Thompson, originally produced by Auto-Ordnance of [[West Hurley, New York|West Hurley]], New York for the civilian collector's market from 1974 to 1999. It has been produced since 1999 by Kahr Arms of [[Worcester, Massachusetts|Worcester]], [[Massachusetts]]. It is officially known as the "Thompson Semi-Automatic Carbine, Model of 1927A1." The internal design is completely different to operate from the closed bolt and the carbine has a barrel length of {{convert|16.5|in|mm|abbr=on}} (versus open bolt operation and barrel length of {{convert|10.5|in|mm|abbr=on}} for the fully automatic versions). Under federal regulations, these changes make the Model 1927A1 legally a rifle and remove it from the federal registry requirements of the [[National Firearms Act]]. These modern versions should not be confused with the original semi-automatic M1927, which was a slightly modified M1921 produced by Colt for Auto-Ordnance.

The Model 1927A1 is the semi-automatic replica of the Thompson Models of 1921 and 1927. The "Thompson Commando" is a semi-automatic replica of the M1928A1. 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====
[[File:BATFE Firearm Classification Letter.jpg|thumb|Auto-Ordnance 1927A5 DOJ BATFE Firearm Classification Letter]]

The Model 1927A5 is a semi-automatic, .45 ACP pistol version of the Thompson originally produced by Auto-Ordnance in West Hurley from the 1970s until the late 1980s or early 1990s. It featured an aluminum receiver to reduce weight. It has since been replaced with the Kahr Arms TA5 Pistol, which features a 10.5" barrel and steel receiver, unlike the 1927A5's 13" barrel and aluminum receiver.

As per the NFA (National Firearms Act of 1934), the "1927A5 .45 ACP Pistol" is simply classified as a "Firearm" (Any type of firearm with an overall length of 26" or greater, that does not have a buttstock) as it neither fits the definition of a Pistol or Rifle under federal law. This categorization also legally allows it to have 1921 or 1928 style foregrip equipped, unlike other "pistol style" Thompson variants, without an AOW (Any Other Weapon) Tax Stamp.

====1928A1 LTD====
The 1928A1 LTD is a civilian semi-automatic conversion by Luxembourg Defense Technology (LuxDefTec) in Luxembourg. They are made from original 1928A1 guns of various appearance (with or without Cutt's compensator, ribbed or smooth barrels, adjustable or fixed sights), that were imported [[Lend-Lease]] guns from Russia.

===Export variants===
====BSA Thompsons====
In an attempt to expand interest and sales overseas, Auto-Ordnance entered into a partnership with and licensed the [[Birmingham Small Arms Company|Birmingham Small Arms Company Limited]] (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 9mmP and [[7.63×25mm Mauser|7.63mm Mauser]] 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.<ref>{{cite web|url=http://www.gotavapen.se/gota/artiklar/kpist/stengun.htm |title=Submachine guns of UK – BSA Thompson 1926 – Thompson 1928A1 – Lanchester – Sten and Sterling |publisher=Gotavapen.se |date=2010-09-08 |access-date=2011-12-25}}</ref>

===RPB Thompsons===
====Special purpose variant====
A special purpose machine pistol variant of the Thompson is manufactured by RPB Industries of Atlanta.<ref>{{cite web |url=http://img822.imageshack.us/img822/8272/3053620dzpobzua.jpg |title=B&W photo of "Special purpose" Thompson|website=img822.imageshack.us |access-date=17 January 2022 |archive-url=https://web.archive.org/web/20120206075121/http://img822.imageshack.us/img822/8272/3053620dzpobzua.jpg |archive-date=6 February 2012 |url-status=dead}}</ref>

====Suppressed variant====
A version with a threaded barrel for suppressors, side folding stock, and modified sights.{{citation needed|date=August 2023}}

===Thompson clones===
Similar weapons were manufactured by Apache Arms, Eagle Gun Co., Volunteer Enterprises Inc,<ref>{{cite web | url=https://patents.google.com/patent/US3695143A/en?oq=3695143 | title=Firing mechanism for semiautomatic firearms }}</ref> and Spitfire MFG Co.<ref>{{cite web | url=https://www.forgottenweapons.com/spitfire-the-semiauto-that-became-a-machine-gun/ | title=Spitfire: The Semiauto That Became a Machine Gun - Forgotten Weapons | date=9 November 2021 }}</ref><ref>{{cite web|last=Dabbs|title=The Old Spitfire SMG: An Unexpected Submachine Gun|first=Will|url=https://www.firearmsnews.com/editorial/spitfire-smg-unexpected-submachine-gun/521841 |date=April 15, 2025|website=www.firearmsnews.com}}</ref>