Skip to main content

Thompson Submachine Gun

Thompson Submachine Gun


A machine gun is a weapon that fires a continuous stream of bullets as long as the trigger is held down. Many inventors worked to come up with such a gun, and early models are the well-known Gatling gun, used prominently in the American Civil War, and Hiram Maxim's fully automatic weapon, patented in 1883. Machine guns of various makes were instrumental in the trench battles of World War I. After World War II, the machine gun was for the most part replaced by different types of more powerful automatic assault rifles. The lightweight machine gun known as the "Tommy gun," or Thompson submachine gun, was developed for use in World War I, and then marketed to law enforcement personnel. It became notorious as the gun of choice of gangsters in the 1920s and 1930s. It is still manufactured, finding a market primarily with gun collectors.


The gun invented by Richard Jordan Gatling in 1862 was the first widely used weapon of the machine gun type. The Gatling gun was not strictly a machine gun, as it was not completely automatic. Its rotating barrel had to be cranked by hand. Ammunition was fed into the Gatling through a top-mounted hopper. It could fire a thousand rounds a minute. American arms inventor Benjamin Berkeley Hotchkiss came up with an improved Gatling-type gun in 1872. Both the Hotchkiss and the Gatling were made obsolete by the invention of the Maxim machine gun in 1883. The Maxim was fully automatic, firing continuous rounds powered by the recoil energy of the exploding shell. Other early machine guns were John Browning's Browning Automatic Rifle of 1892, and an improved version of the Browning developed by an American army colonel Isaac Newton Lewis in 1911. By the Boer War of 1899-1902, the effectiveness of the machine gun was well demonstrated, and European countries adopted various weapons of Maxim, Hotchkiss, and Lewis in the years leading up to World War I. These machine guns were heavy, needed to be supported by a block or tripod, and they tended to overheat quickly, requiring some sort of cooling system.

The inventor of the Thompson submachine gun was Kentucky-born Army officer John Taliafeffo Thompson. He was born into a military family, and spent his youth on military bases across the United States. He graduated from the military academy West Point in 1882 and then entered the army. By 1890 Thompson was working in the Ordnance Department, where he remained for the rest of his career. Thompson became a specialist in small arms, and by 1903 he was working on modernizing many of the Army's weapons designs. He developed a new model rifle based on the German Mauser in 1903, and in 1907 he was put in charge of small arms design, development, and production in the Ordnance Department in Washington. Thompson's dream was to convince the United States Army to adopt or develop an automatic rifle, but his ideas were considered radical. The machine gun's several inventors had all gone to Europe to market their weapons, and the U.S. Army remained uninterested. Thompson eventually retired from the army in 1914, and went to work for the Remington Arms Corporation, one of the leading American weapons manufacturers. At Remington he pursued plans to design his own automatic rifle. Through personal contacts, Thompson met business magnate Thomas Fortune Ryan, and the financier agreed to provide the inventor with capital. In 1916, Thompson launched a new company, the Auto-Ordnance Corporation, to develop, manufacture, and market a new automatic rifle. This firm, based in New York, contracted with a Cleveland machine-tool firm, Warner & Swasey, to build and test its prototypes. Auto-Ordnance's first attempts at an automatic rifle failed. In 1917, with the European countries engaged in trench warfare in World War I, John Thompson decided to opt for a new design entirely. This was to be a small, hand-held machine gun. The Maxims and other machine guns in use in World War I were large, relatively immobile weapons that were used primarily defensively. Thompson envisioned a gun of similar swift firepower, that soldiers could run with, and so use in offensive assaults.

Auto-Ordnance began working feverishly on this "miniature" machine gun. The first workable designs were done in 1918, and the company made several prototypes and got them ready to ship to American troops overseas. The prototypes reached the dock in New York the day the Armistice was signed, and Auto-Ordnance thus lost out on its intended market. The company went back to work, trying to modify the gun for use other than in trench warfare. In 1919 the company unveiled its Thompson submachine gun, the "sub" indicating that it was much smaller than the massive machine guns used in Europe. The premier United States gunmaker Colt agreed to manufacture the Thompson, and the first guns were ready in March, 1921. Though Auto-Ordnance hoped to get a large order from the U.S. Army, it instead found eager takers in countries like Honduras and Panama, where the guns were used to solve labor disputes. Within months of the gun's introduction, the Thompson found its way to underground fighters of the Irish Republican Army (IRA). Auto-Ordnance marketed the gun heavily to police departments, touting the "pocket machine gun" as a great way to stop bank robbers and other motorized bandits. Unfortunately, it was these criminals who seized on the merits of the Tommy gun. In 1925 gangsters in Chicago used Thompsons in vendettas, finding them ideal for quick killing from a safe distance. The submachine guns were apparently easily and legally available at sporting goods stores. Notorious gangster Al Capone supposedly stopped at a Chicago sporting goods store to get a gun, and Capone's first known Tommy-gun killing followed on April 27, 1926. The guns spread through the underworld, first in other parts of the Midwest, and then to New York. They were used in Chicago's notorious St. Valentine's Day Massacre in 1929 and carried by renegade killers Bonnie and Clyde in the 1930s.

During the 1930s, the Tommy gun continued to be identified with desperados, gangsters, and bank robbers. In 1932, Auto-Ordnance at last convinced the United States Army to buy its guns, but the Army bought only small quantities. However, on the eve of World War II, the company suddenly received an order from France for 3,000 Tommy guns. The French order was soon followed by a British one, and the U.S. Army too ordered over 20,000 Thompsons in 1940. Colt refused to manufacture more of the submachine guns because of the bad press the weapon had received, and the Thompson was redesigned and somewhat simplified to fill the World War II orders. The Thompsons of the 1940s were manufactured by a company in Bridgeport, Connecticut, where they were the only light machine guns being mass-produced by any of the Allied countries. But even the new, improved design was soon obsolete. By the end of the war, the Thompson had been surpassed by the cheaper, lighter British STEN gun and its United States counterpart, the M3. The M3 was known as the "grease gun," an inelegant thing that was made of stamped metal, welded together. Ugly as it was, it could be mass-produced for a fraction of the cost of the Thompson.

After the war, demand for the Thompson was practically gone. Auto-Ordnance Co. changed hands several times, always on the verge of bankruptcy. In the 1970s, the company was acquired by a former employee, Ira Trast, who redesigned the classic Thompson as a semi-automatic weapon. The intended market was mostly gun enthusiasts who wanted a working gun that looked like the infamous gangster weapon. In 1999 the company changed hands again. It was bought by Kahr Arms in Blauvelt, New York. In order to produce a historically accurate gun, Kahr researched the original engineering drawings for the Thompson, digging through records going back to 1919. Kahr then used modern computer design and drafting techniques to produce completely new engineering drawings based on the old designs. Thompson submachine guns are now an interesting blend of old and new technology. Parts are machined by precision instruments controlled by computers, and then the guns are carefully assembled by hand by trained artisans.

Raw Materials

The raw materials for Thompson submachine guns are mostly steel, with lighter alloys for small and flexible parts such as springs. The stocks are made of walnut, a traditional hardwood for gun manufacturing.


The original design process for the Thompson was quite lengthy, and involved numerous drawings and prototypes. The gun was redesigned for use in World War II to make a simpler model that was easier to mass-produce. The Thompsons produced after World War II were assembled out of surplus parts by a company that had bought Auto-Ordnance's inventory. When the parts inventory began to run low, Auto-Ordnance was sold to Kahr Arms, a manufacturer of guns, other weapons, and parts, as well as many other metal products. At this point, Kahr wished to make complete Thompson guns out of new parts. Kahr's engineers consulted the scores of original drawings for historical accuracy, and also went through a process known as reverse engineering.

In reverse engineering, engineers take apart a finished product and figure out how it was made. Drawings are made from already available parts, instead of new parts being made from engineers' drawings. To make the Thompson according to modern methods, a drawing for each part was produced using computer software known as computer aided design, or CAD. Next, a separate set of drawings were made, called machine or shop drawings. These are blueprints that show exactly how each part needs to be cut. These drawings are converted to computer codes that can be read by the actual cutting machines.

Richard Jordan Gatling was born in 1818 in Hertford County, North Carolina. Gatling helped his father develop machines for sowing and thinning cotton. In 1839 Gatling invented a screw propeller for ships and went on to develop agricultural machines, such as a hemp-breaking device and a steam plow.

When the Civil War began in 1861, Gatling focused his efforts on armaments. In 1862 he invented the weapon that has bore his name ever since, the Gatling gun. Considered the first practical machine gun, the Gatling gun was capable of firing 250 shots per minute. It consisted of 10 breach-loading rifle barrels—cranked by hand—rotating around a central axis. Each individual barrel was loaded by gravity feed and fired while the entire assembly evolved. Cartridges were automatically ejected as the other barrels were fired. It was operated by two people: one fed the ammunition that entered from the top, and the other turned the crank that rotated the barrels. At first, the Union Army was uninterested in Gatling's invention, but General Benjamin Butler (1818-1893) eventually bought several Gatling guns. They worked so well on the battlefield that the government finally agreed to adopt them in 1866, but by then the war was over.

After the war, Gatling continued to improve his gun. Eventually, it was capable of firing 1,200 shots per minute at all degrees of elevation and depression. Gatling's gun was used all over the world and remained in the United States military arsenal until 1911.

The Manufacturing Process

Cutting the steel

  • 1 The manufacturer first receives its raw material at the factory as steel bars. These are cut by a number of specialized machines. The machines read the computer-generated blueprints and cut exactly to specification. The component parts of the gun have been designed so that they can be produced in only one or two operations, thus cutting down the possibility of deviation from the desired specifications. Some of the main parts of the Thompson that are cut from solid steel are the barrel, the receiver, the bolt, and the frame.

Other metal parts

  • 2 Not every part needs to be cut from solid steel. Some smaller parts are stamped. These are done by a sub-contractor who specializes in stamping. Large stamping machines press down on sheets of metal, working something like a cookie cutter. Springs are also purchased from a sub-contractor who specializes in spring manufacturing.

The stock

  • 3 The stock is made of walnut. This is made by a sub-contractor according to the gun manufacturer's design specifications. Workers use wood-cutting tools to cut and shape the stock from walnut boards, and ship them to the machine gun maker.


  • 4 The Thompson gun has a total of between 60 and 70 parts total. Rather than workers assembling the whole gun at once, the process is broken down into five main subassemblies. Workers at the factory are divided into different subassembly stations. Parts belonging to a particular subassembly are set out, and workers fit parts together by mating surfaces and/or securing parts with screws. Workers are selected for jobs because they have a background in firearms, and they go through a three-month internship before they are fully qualified. Workers are paid by the piece, and so they strive to be fast as well as accurate.

Final assembly

  • 5 Other workers put the entire gun together from the finished subassemblies. Because of the high precision of the machining, parts fit neatly into each other. They are snapped into place and secured with screws. The wooden stock is screwed on last, and the gun is cleaned and polished. Then the finished Thompson moves to a quality control area for a final check.

Quality Control

The maker of Thompson submachine guns works under international standards for manufacturing quality. These are standards that apply to the metal machining techniques used, whether the end product is a gun or an exercise machine. To list itself as a factory following these standards, the manufacturer submits to random audits of its facilities several times a year. So the entire facility follows strict guidelines for quality control. As far as specific quality control tests for the Thompson, the guns undergo tests for function and for cosmetics. Each finished gun is carefully inspected for obvious outward flaws such as scratches or blemishes on the stock. And each gun is test-fired. Quality control workers at a test firing range shoot off six or seven rounds from each gun. Then the guns are wrapped, boxed, and distributed to wholesalers.

The Future

Modern guns have taken the place of Thompson submachine guns for warfare and other uses. But they have historical significance, and may be collected by gun enthusiasts for that reason. Although the design and inner workings of the Thompson has changed for modern manufacturing, it is the distinctive outward appearance of the gun that will surely remain unchanged in the future. Manufacture of the Thompson will likely continue as long as our fascination with history and the underworld is alive.

Where to Learn More


Helmer, William J. The Gun that Made the Twenties Roar. London: Macmillan, 1969.

Hosley, William. Colt: The Making of an American Legend. Amherst, MA: University of Massachusetts Press, 1996.


Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Thompson Submachine Gun." How Products Are Made. . 17 Mar. 2018 <>.

"Thompson Submachine Gun." How Products Are Made. . (March 17, 2018).

"Thompson Submachine Gun." How Products Are Made. . Retrieved March 17, 2018 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.