The Thompson submachine gun, a product of finely machined hand craftsmanship, was completed too late to fill its intended role as a WW1 trench sweeper but saw service on all Allied fronts in WW2. Known colloquially as the Tommy gun, this impressive SMG also found fame on the streets of Prohibition-Era America.

Two documented law enforcement Model 1921 Tommy guns for sale.

Rock Island Auction Company offers the finest selection of Class III firearms around, including collecting rarities like the Stoner 63, the German MG34, and the immensely desirable M240. With growing popularity and a finite supply, there's no better time to get your hands on some of these desirable heavy hitters, including iconic classics like the Tommy gun.

The records in Herigstad's "Colt Thompson Submachine Gun" show this 1921 Tommy gun as having been shipped to Supervisor Lockwood of the Leonia, New Jersey Police Department on November 7, 1930.

What is a Tommy Gun?

A Tommy gun is a select fire submachine gun with a milled steel receiver that was initially built around the Blish Lock delayed-blowback action. Designed to chamber the .45 ACP cartridge, most examples of the early Thompson platform include features like front and rear pistol grips, a finned barrel, a detachable buttstock, and compatibility with a 20-round stick magazine and a 50 and 100-round drum mag. While the M1921 Thompson could spew lead at a blistering 1,500 rpm, its successors reduced the firing rate to more manageable levels.

A Tommy gun for sale with documentation and accessories, this Model 1921 in “1921AC” configuration shipped to Hot Springs, Arkansas in 1929, and is later listed as shipping to the Greenville, South Carolina Police Department in 1932, during the heart of Prohibition.

Technical details aside, the Tommy gun is one of the world's most famous guns thanks to the weapon's Hollywood coverage and depiction in foreign propaganda posters. Even a century after the Thompson's debut, the gun's profile is still recognized the world over.

A documented Rock Island County Sheriff's Department Colt Model 1921 Tommy gun for sale.

When was the Tommy Gun Invented?

The first Tommy gun prototype, called the “Persuader,” was completed in late 1917. Around 40 more prototypes followed, each including a series of design modifications. The idea behind the Tommy gun was conceived two years earlier by John Taliaferro Thompson, a retired army Colonel working as Chief Engineer of Remington Arms Company, when he obtained the patent of Navy Commander John Bell Blish for a unique breech locking mechanism.

While the Tommy gun was invented in 1916 and the first prototypes were completed in 1917, official production started four years later with examples like this early production Colt Model 1921 shipped to the Nelson Hardware Company of Roanoke, Virginia on December 5th, 1921, for delivery to the Roanoke Police Department.

In 1916, Thompson partnered with financier Thomas Fortune Ryan to create the Auto-Ordnance Corporation. As WW1 raged in Europe, the U.S. military's need for advanced weaponry was greater than ever, and Thompson envisioned a fully automatic “trench broom” that could help infantrymen break the bloody stalemates of modern warfare.

This Model 1921AC Tommy gun was shipped to Kay County Sheriffs Office in Newkirk, Oklahoma on August 10th, 1933.

The Armistice signed on November 11, 1918 ended the Great War and lessened the opportunity for Auto-Ordnance to score major military contracts for their new weapon. Thompson instead set his sights on the civilian and law enforcement markets. The “Thompson Submachine Gun, Model of 1921,” the first commercial production run for the model, was manufactured by Colt and saw 15,000 units.

A cased Model 1921/1928 U.S. Navy Overstamp Tommy gun for sale this August, documented as shipped to the Sheriff's Office of Beaver County, Pennsylvania

What Caliber was the Tommy Gun?

In the early stages of developing the Tommy gun, Auto-Ordnance engineers Oscar V. Payne, Theodore H. Eickhoff, and George E. Goll discovered that rifle calibers like .30-06 failed to properly extract with the Blish Lock system unless they were oiled. Later tests revealed that the .45 ACP cartridge had no such issues. In September of 1917, Thompson approved .45 ACP as the official Tommy gun caliber, a cartridge he'd helped test during U.S. Army pistol trials 13 years earlier.

Manufactured in the 1970s/1980s as part of the “A” suffix serial range, this Auto-Ordnance M1928 Tommy gun is chambered in .45 ACP.

Though the Tommy gun was beat to market by the German MP18, it was the first firearm to include the term submachine gun in its name thanks to the weapon's use of the .45 ACP pistol caliber. Auto-Ordnance would eventually offer .22 caliber conversion kits for the Thompson, and in the 1980s a select number of fully automatic Tommy guns chambered in .22 LR were produced, dubbed the Auto-Ordnance Model 1928 A22. A limited number of fully automatic FBI Tommy guns were converted to 10mm in 1990. Today, semiautomatic Tommy guns can be found in a variety of chamberings.

A gold-plated Tommy gun. This Auto-Ordnance WW2 commemorative Thompson 1928 with a glass-topped commemorative display case and related paperwork is one of only 85 fully automatic examples produced in the series.

Mobster Tommy Guns

Today, the Tommy gun is synonymous with the Roaring 20s and the Great Depression thanks to its use by motorized robbers and the lawmen on their tail. Though the Thompson was initially marketed to ranchers and advertised to police departments as an “Anti-Bandit Gun,” the weapon ended up becoming a favorite of the gangers during America's Public Enemy Era.

This historic Colt Model 1921 Tommy gun, sold by RIAC in 2015 for $80,500, is documented to legendary FBI Agent Melvin Purvis during the final pursuit and death of Charles Arthur "Pretty Boy" Floyd, Public Enemy Number One.

The Tommy gun provided a substantial firepower advantage to those with deep enough pockets to afford one. Notable users include criminals like Bonnie and Clyde, Baby Face Nelson, and Machine Gun Kelly, and the Capone Gang toted a pair of Thompsons during the brutal St. Valentine's Day Massacre. The FBI and law enforcement agencies around the nation armed themselves with Tommy guns in an effort to keep up with their criminal adversaries.

The bandits and gangsters of the 1930s relied on a variety of weaponry, including heavy hitters like the Tommy gun and BAR. The Remington Model 11 is attributed to "Pretty Boy" Floyd and a Winchester Model 1895 that belonged to Bonnie and Clyde gang member Floyd Hamilton.

Tommy Gun Nicknames

The image of the mobster Tommy gun inspired numerous colorful nicknames for the weapon during America's gangland era. Some common monikers include “trench broom,” “street sweeper,” “rat-tat-tat,” “chopper,” “drum gun,” “Chicago piano,” “Chicago organ grinder,” and “Chicago typewriter.”

A Colt Thompson M1921 submachine gun shipped as a single item to Chief of Police James Dinan of the Edgewater, New Jersey Police Department on October 30, 1930. Includes case and accessories.

The platform's most well-known nickname, “Tommy Gun,” is a blue-collar shorthand for Thompson. Ever the businessman, John Thompson trademarked the Tommy gun term as its popularity grew, and the top of the receiver on a limited run of Savage Arms produced M1928 and M1928A1 Thompson's are marked with “TOMMY GUN” on top of the receiver.

A Savage Arms Corporation M1928A1 sold at RIAC in 2012, marked “Tommy Gun” on the receiver.

Adoption of the Tommy Gun

Auto-Ordnance only sold around 6,000 Tommy guns in the platform's first seven years on the market. Thompson's dream of attracting major military contracts seemed like a lost cause, although a deadly mail truck robbery in 1926 spurred President Coolidge to authorize the purchase of 250 Tommy guns for the U.S. Marine Corps to assist in protecting post offices and mail transportation.

The following year, the Marines deployed some of these newly acquired Thompsons during the Nicaraguan Campaign. Based on feedback from the Marine Corps, Auto-Ordnance made several changes that resulted in the Thompson M1928, including slowing down the firing rate with a heavier actuator. Another addition was the standardization of the Cutts Compensator. An optional accessory offered in 1926, the Cutts Compensator was a .45 ACP muzzle brake that increased the Tommy gun's accuracy.

An outstanding, documented law enforcement shipped 1921/1928 U.S. Navy overstamp Tommy gun.

In 1928, the Navy Bureau of Ordnance formally adopted the Thompson. Despite the weapon's success with the Navy and Marines, a U.S. Army test in February of 1928 concluded the Thompson was “an undesirable weapon, effective only at short range.” Their opinion would change ten years later when the threat of war once again reared its head in Europe and Asia.

An exceptional example of a Tommy gun for sale, this documented law enforcement shipped Colt Model 1921/1928 includes U.S. Navy overstamp markings.

The Tommy Gun in WW2

Every iteration of the Thompson M1928 saw service in WW2. Savage Arms was contracted in late 1939 to help produce the M1928, with many being purchased by the British military. The U.S. Army had adopted a parkerized version of the Tommy gun the previous year designated the M1928A1. In 1940, the U.S. Army ordered 20,450 Thompson SMGs, with over 300,000 more the following year for America and her allies.

To meet surging demand, Auto-Ordnance developed the U.S. M1 Thompson in 1942, a streamlined version of the platform intended to reduce production time and cost.

The U.S. M1 Thompson, a streamlined version of the platform developed during WW2, offered American officers and NCOs in the European and Pacific theaters a devastating close-quarters combat option. Available this August.

The M1 was produced with a shorter barrel and lacked cooling fins and the Cutts Compensator. Drum magazine compatibility was eliminated, the buttstock became fixed, and the charging handle was moved from the top to the side of the receiver. The Blish Lock was dropped completely from the M1 design in favor of a simple blowback system. Initial military testing calculated the average firing rate for the M1 Thompson at 775 rpm, with subsequent tests recording speeds as high as 920 rpm.

The M1A1 update incorporated a fixed firing pin machined to the bolt face in favor of its predecessor's interchangeable firing pin, which modestly reduced the M1A1 Thompson's firing rate. The Tommy gun offered American officers and NCOs in the European and Pacific theaters a devastating close-quarters volume fire option to complement the more frequently equipped M1 Garand and M1 carbine. The Thompson was also issued to vehicle and tank crews before the M3 “grease gun” became available.

The M1 Thompson served in every theater of WW2.

The Tommy gun's high price point led to the British adopting the STEN in 1941 and America adopting the M3 in 1943, both cheaper sheet steel SMGs. The Thompson continued to roll off the assembly line until early 1944, with a staggering 1,750,000 produced during the war.

Classified as a “Limited Standard,” the Tommy gun saw service during the Korean War with America and its allies due to the weapon's plentiful supply. During the War in Vietnam, Thompsons were shipped to the South Vietnamese in the early years of the conflict and carried by some American military advisors. Though South Vietnamese soldiers came to prefer the lighter M16 rifles, the Tommy gun continued to serve as an auxiliary weapon throughout the conflict.

A U.S. Guide Lamp M3 "grease gun."

How Much is a Tommy Gun?

The price of a Tommy gun in 1921 was $200.00, or $3,246.49 in today’s currency. For reference, a Ford Model T cost $310.00 during the same period, with early semi-automatic rifles like the Winchester Model 1907 being offered for only $58.00. A Tommy gun with accessories like additional stick or drum mags would raise the price even further.

Due to limited supply and a high demand in the collecting community, machine guns have soared in value, particularly Tommy gun prices. At the time of writing, the low end for purchasing a Tommy gun is around $30,000 and steadily rising. Many examples are regularly achieving mid-to-high five figure price tags at auction, especially high-condition pieces that include their original case and accessories like the Colt M1921 Thompson pictured below.

How much is a Tommy gun? This Colt M1921 Thompson realized $94,000 in Rock Island Auction Company's August 2022 Premier Auction, demonstrating a rising price ceiling for the platform.

The Tommy Gun Today

While advancements in materials and manufacturing techniques allowed lighter, cheaper, and more compact submachine gun models to exceed the Thompson in performance, the style and craftsmanship of the classic Tommy gun continue to appeal to arms enthusiasts around the globe.

Up until the Firearm Owners Protection Act of 1986, Auto-Ordnance continued to assemble fully automatic Tommy guns using surplus components produced during WW2. The gold-plated Thompson Korean War commemorative pictured below, manufactured for distribution by the American Historical Foundation, is one such example.

A gold Tommy gun for sale, this post-WW2 Auto-Ordnance Thompson was produced in the 1928A1 configuration and has been outfitted and decorated as a commemorative piece for the Korean War.

Auto-Ordnance changed hands numerous times throughout the years and was purchased in 1999 by Saelio Enterprises Inc., the parent company of Kahr Arms. At the time of writing, Kahr Arms offers a variety of modern Tommy gun variants for sale in the form of the 1927A-1 family, a closed bolt, semi-automatic version of the classic design with an extended barrel and fixed buttstock.

An Auto-Ordnance Model 1928 Tommy gun in the "A" serial range, this example includes a 100-round Type "C" drum mag.

Kahr Arms models include colorful names like “Commando,” “Tanker,” and “Bootlegger Special,” with several featuring extensive gold plating. Though these modern Tommy gun replicas might lack the giggle-switch of their vintage counterparts, they offer a unique range experience in their own right while capturing some of the essence of the original Tommy gun.

A modern Tommy gun for sale, a semi-automatic Auto-Ordnance Model 1927 pistol.

The Tommy Gun in Hollywood

The image of the mobster Tommy gun was immortalized by Hollywood beginning in the early 1930s with films like 'Little Caesar' and 'Pardon Us.' The Thompson continued to play a starring role in countless movies and television productions over the decades, with recent appearances in 'Peaky Blinders' and Yellowstone prequel '1923.'

Thanks to Hollywood and popular culture, the name Tommy Gun has become famous around the world.

In 1972's 'Godfather,' perhaps the Tommy gun's most notable movie outing, Sonny Corleone is gunned down by hitmen wielding the famous weapon. One of those screen-used Tommy guns, formerly of the Stembridge Gun Rental collection, was sold by Rock Island Auction Company in 2020.

A documented Hollywood screen-used Colt Model 1921 Thompson submachine gun sold for $43,125 in December of 2020.

Tommy Guns for Sale

Due to its sleek lines, remarkable craftsmanship, Hollywood exposure, and historic connection to Prohibition and WW2, the Tommy gun stands as one of America's most iconic firearms. For collectors, historians, and anyone interested in engineering and the evolution of the machine gun, the Thompson is an absolute must have, and the best place to find an original Tommy gun for sale is Rock Island Auction Company.

Manufactured in the 1970s/1980s as part of the "A" suffix serial range, the Auto-Ordnance 1928 Thompson is virtually a perfect reproduction of the vintage Tommy Gun.

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An exceptional example of a Tommy gun for sale, this documented law enforcement shipped, U.S. Navy overstamp Colt Model 1921/1928 includes desirable accessories like a 50-round "L" drum magazine and four 20-round stick magazines.