Umarex Thompson M1A1 Part 1

Umarex Thompson M1A1 Part 1

America’s Legendary WWII Submachine Gun

By Dennis Adler



The Thompson M1A1 was the last version of the Thompson design and the model introduced during WWII. The .45 ACP select-fire submachine gun was also used during the Korean War and during the Vietnam War. Approximately 1.75 million Thompson submachine guns were manufactured in all versions. Today’s Auto Ordnance Thompson models are all semiautomatic. The WWII era M1A1 was the inspiration for the Umarex Legends M1A1, at the bottom opposite a WWII example.

If you go back a couple of years in the Airgun Experience archives and look at reader comments, you will find a lot of people had a wish list for new models, especially after the Umarex Legends German MP40 Submachine Gun was introduced, and at the top of most lists was the legendary WWII M1A1 – the Thompson submachine gun. The M1A1 was the U.S. military’s last version of a design originated back in 1918 by General John T. Thompson, and developed by his company, the Auto-Ordnance Corporation. Originally intended for U.S. and allied troops during WWI, by the time the design was ready the war was over.  

Earlier, or if you prefer, “classic” style Thompsons from the 1920s and 1930s (shown with the 50-round drum magazine) had the finned barrel to help dissipate heat and the forward pistol grip. Also note that the earlier designs, prior to the M1A1 had the bolt handle on the top. (Photo courtesy Rock Island Auction Co.)

Thompson had a long career as a U.S. military officer and arms designer, having been instrumental in overseeing the development of the Springfield M1903 rifle and the adoption of the .45 ACP Colt 1911 pistol as the standard issue military sidearm. With few military contracts in the offing after The Great War, further development of the Thompson design led to the first civilian model in 1921, which were built under contract by the Colt’s Patent Firearms Mfg. Co. These are different from the later military Model M1A1, but are the “classic Tommy Gun” of the 1920s, with the finned barrel and forward pistol grip. Thompson promoted it for lawmen and bank guards, among others in law enforcement, as the “anti-bandit gun.” Of course, it turned out that the bandits made better use of it, including gangsters Al Capone, John Dillinger, Machine Gun Kelly (no further explanation needed), Baby Face Nelson, Pretty Boy Floyd, Bonny and Clyde among other well financed outlaws of the era. The Thompson was not an everyman’s or every bandit’s submachine gun at a price of $200 in 1921; that’s equivalent in purchasing power to $2,870 in 2020. The Thompson was even a little pricey for the U.S. government back in the 1920s and initially only the U.S. Postal Service purchased them (around 200 guns, magazines, and accessories) for Postal Inspectors guarding the mail from thieves and organized crime.

The pre-M1A1 models all used a more complex action (the Thompson-Blish design) which was more expensive to manufacture. In the 1920s, a Thompson retiled for $200 making it one of the most expensive guns on the market. The designs had a muzzle break and easily removed shoulder stock. (Photo courtesy Rock Island Auction Co.)

The next big customer was the FBI in 1933 (which continued to use Thompsons of various models, including the later M1A1, up until 1970). The U.S. military adopted the M1928A1 model in 1938 (which still had a muzzle break and cooling fins on the barrel), and during WWII the more affordably built M1A1 version, which at the height of the war in 1944, the U.S. was purchasing from Auto Ordnance for only $45 apiece. The cost saving and manufacturing changes in the Thompson design were developed at Savage Arms, and the M1 (M1A1) design was adopted by the Army in April 1942. The guns were manufactured both by Savage and Auto Ordnance for the military. The M1 and M1A1 had a barrel without cooling fins, a slower rate of fire (600 rpm), a simplified rear sight, wood forearm, and only used the long 30-round box magazines. The guns also employed a straight blowback action design (less complicated than the original Thompson-Blish action), and moved the charging handle to the right side of the receiver, instead on the top.

The Thompson design was not ready for the U.S. military until after the end of WWI, and with few government contracts, Auto Ordnance turned to the law enforcement market in the early 1920s declaring the Thompson the Anti-Bandit Gun in advertising. At this point in time (prior to 1934) the ownership of automatic weapons was not restricted. The Thompson’s greatest restriction from the general public was its price.

Civilian use of the Thompson in the 1920s and 1930s was not promiscuous but their use by organized crime led to President Franklin D. Roosevelt signing the Gun Control Act of 1934 (America’s first gun legislation) which made the possession of short-barrel shotguns and rifles, and fully automatic weapons like machine guns illegal unless one passed a stringent background check and paid a tax and registration fee of $200, which pretty much made the manufacturing of quite a few guns (like the Ithaca Auto & Burglar sawed off shotgun, among others,) unprofitable for most gunmakers.

Further improvements were made to the Thompson design with the M1928A1 which introduced the wood forearm and simplified rear sight. These were the first models adopted by the U.S. military.
By the start of WWII, a more economical to manufacture Thompson was available, the M1A1 adopted by the U.S. military is 1942 and used extensively throughout the war. The M1A1 could only use the upright box magazines, which were offered in 20 round or 30 round capacities. The older M1928A1 models used the 50-round drum magazines which were determined too cumbersome and heavy to handle in the field. (Photo courtesy Rock Island Auction Co.)
The M1A1 saw use throughout WWII. This picture was taken during USMC action on Okinawa. (Library of Congress)

The Thompson was unscathed by and large having firmly established itself with the Federal Government, and since organized crime syndicates were already breaking the law, one more offense really didn’t matter. Oddly enough, Bonny and Clyde did not have a Thompson among the guns found in their car when they were cornered on a Louisiana back road in May 1934 and gunned down by lawmen, including retired Texas Rangers Frank Hamer and Maney Gault. Bonny and Clyde did, however, have at least one Thompson that was captured by police in a raid of their Joplin, Missouri, hideout on April 13, 1933. They got the guns but no Bonny and Clyde. The Thompson’s adoption by the U.S. military during WWII and use by the FBI erased most of the gangland stigma of the 1920s and’30s (unless one went to the movies).

Remarkably accurate in appearance, the new Umarex Legends M1A1 duplicates the look and feel of the WWII Thompson.
The CO2 BB magazines have a capacity of 30 rounds to duplicate the WWII models. The internal design is identical to the MP40 CO2 BB magazines but the exterior design (and thus the fit to the individual guns) is unique.

Looked at it today, the M1A1 may not be the classic “Tommy Gun” design of the 1920s, but it was a much more successful gun to manufacture with more than 1.5 million having been built during WWII alone. You would think with that many guns they would be more affordable today (once you pass the background check, pay the transfer fees, etc., or have a Class III FFL) but according to Rock Island Auction Company, an M1A1 Thompson in excellent condition will command anywhere from $16,000 to $25,000. What most people couldn’t afford to purchase in the 1920s for $200, you can’t afford in today’s dollars either. Some things in life are a constant and that makes the Umarex Legends M1A1 Thompson not only a very authentic CO2 version of the WWII model, but an honest to goodness bargain for airgun enthusiasts at an MSRP of $249.95; just a little more than the price of the real thing 99 years ago.

All of the operating features of the WWII M1A1 are accurately reproduced on the Umarex, which is a couple of pounds lighter than the .45 ACP models. Although the forearm, pistol grip and stock look like wood, this is by far the best wood grained injection-molded wood-finish furniture seen on a CO2 model.

In Part 2 we will begin to examine the Umarex Legends M1A1 and spec out its features compared to the WWII model.

5 thoughts on “Umarex Thompson M1A1 Part 1


  1. The long awaited arrival of the King. Nice summary of the Thompson history as well as the nod to the beginning of the Democrat philosophy of gun control. This Thompson should be flaw free and function well since it borrows the already refined mag design of the MP40. Should be the replica of the year. Thought it might have competition from the Springfield M14 but that is a single shot springer like the Mauser. The Thompson looks like a must have. Sniff, do I smell a Combat weathered version?



    • Probably never. What they could do pretty easily would be a Sten bb replica, a Grease Gun, SW 43/44, and the politically incorrect AK. Beretta 93R, and Glock 48, which could be done in pellet version.


  2. To make the stock seem more like real wood?
    (I make this comment not having seen one in person yet, am planning to get one soon).
    I noticed on another website someone said the hollow sound of the stock when the swivels hit it can be eliminated by stuffing rags (‘old socks’) into the buttstock. They said the stock would then ‘sound’ more solid and the gun won’t weigh much more.


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