Umarex Thompson M1A1 Part 2

Umarex Thompson M1A1 Part 2

The devil is in the detail

By Dennis Adler

The M1A1 at the top was sold by Rock Island Auction Co. and written up as follows: This is a very late World War II production M1A1 Thompson Submachine Gun, manufactured by the Auto Ordnance Corp. in Bridgeport, Connecticut. The M1A1 was introduced in April 1942 as a war-expedient/simplified version of the M1928 Thompson Submachine Gun. The war expedient features included the elimination of the barrel cooling fins, Cutt’s compensator, adjustable rear sight and removable buttstock. They also employed a side-mounted cocking handle and a fixed firing pin with a slightly longer bolt which allowed the weapon to be easier and cheaper to manufacture. This example has the standard Lyman “L” type fixed rear sight, horizontal walnut forearm and fixed walnut buttstock. The new Umarex M1A1 is below. No more need be said.

WWII-era M1A1 Thompson SMGs are expensive. Auto-Ordnance still makes the .45 ACP models as semi-autos for a lot less, and those run $1500 to a little over $2000, depending upon the version; M1 Carbine, M1A1-style SBR, or Tanker Model, but the only way to get a select-fire version today, outside of purchasing an original WWII model or an older Auto-Ordnance model, (they built select-fire versions up until 1986), doing the paperwork, (this applies to the new Auto-Ordnance M1 SBR which approximates the M1A1 with a short 10.5 inch barrel), federal background check and transfer fees ($200), is to opt for air and get the Umarex Legends M1A1, which is to say, at this moment in time, the ultimate CO2 subgun on the market. Sorry MP40, this is a much cooler American subgun. There is literally nothing you can say about the look of this new Umarex model that is not positive. Like I said in Part 1, even the wood finished plastic stock, pistol grip and forearm are the most realistic looking pieces ever. Would I like to see a version with real wood? Absolutely, but that would probably raise the price at least another $100 (like the Springfield Armory M1 Carbine). As it stands, as a new 2020 model, there is nothing missing and I can’t think of a better way to kick off the year than with a model that has been on just about every Airgun Experience reader’s wish list for years.

The M1A1 and earlier Thompson submachine guns offered a great advantage to U.S. soldiers carrying the M1911A1 pistol since both used the same ammunition. The same is true with the CO2 models. (Pictured with custom finished Tanfoglio 1911)

The M1A1 Experience

 Recreating famous American and European guns as CO2 pistols, rifles, and the very specialized semi-auto and full auto submachine guns used in WWII, has given airgun enthusiasts what are arguably the most famous designs of the 20th century in a form that can be appreciated for authentic details and enjoyed for sports shooting and collecting. But the historical imperatives of these guns can never be overlooked, the German MP40 was a response to the M1A1 Thompson (and earlier Thompson models), as an example, and both saw service in WWII by the early 1940s. Both are also made today as semi-auto centerfire guns, so the designs are not obsolete, but rather make the CO2 models all the more significant.

The comparison goes without saying; the MP40 was Germany’s answer to the Tommy Gun. A bit less elegant than General John T. Thompson’s designs at Auto-Ordnance and the updated M1A1 version designed at Savage Arms, these two remain in both their centerfire form and as CO2 models, the most recognized submachine guns of WWII and variations of both are still made to this day as centerfire semi-autos.
The Umarex uses a copy of the M1A1 standard Lyman “L” type fixed rear sight.

The WWII era Thompson was easier to handle than its predecessors. As a select-fire submachine gun sharing ammunition with the Colt Model 1911A1, ammo supplies in the field were easier to manage, and though heavy at 10 pounds (empty), it was handier than some heavy rifles, and perfectly designed for close quarter battle situations, especially where U.S. forces found themselves fighting an urban war from building to building, and block by block liberating cities under German occupation.

The M1A1’s fixed battle sights were optimal at 50 yards. The gun had an overall length of 31.9 inches with a 12-inch barrel. It was actually fairly compact. The Umarex Legends M1A1 measures 31.75 inches with a 12-inch barrel, and comes in a little lighter than the WWII model at 7.75 pounds.

The modern M1A1-style Thompson semi-auto built by Auto-Ordnance today, still has the same dimensions as the WWII model. Again, the authenticity of design is evident in the Umarex model below.

Now, let us look at that in comparison to the German MP40 and Umarex MP40 CO2 model. In overall length the MP40 submachine gun measured 32.8 inches with the folding metal stock extended, 24.8 inches with the stock folded, and weighed in at 8 pounds 13.8 ounces empty. Barrel length measured 9.9 inches. The Umarex is very accurate in these details and no lightweight at 7 pounds, 14 ounces empty. The air rifle’s overall length with the stock extended is 32.75 inches and 24.5 with the stock folded. The smoothbore .177 caliber barrel is 9.0 inches and recessed inside a correct length 9.9 inch outer barrel with a full size muzzle. Overall, more than close enough considering the number of different factories that built MP40s during WWII. In effect, the two famous submachine guns of WWII, the M1A1 and MP40 are very much equals, with an advantage going to the M1A1, which could be fired either semi-auto or full auto, whereas the WWII MP40 was full auto only, making it difficult to control, and fired 9x19mm rounds, vs. the Thompson’s heavy hitting 230gr. hardball .45 Auto. As airguns, the M1A1 and MP40 are also equals.

At 7.75 pounds the Umarex M1A1 is no lightweight. It feels and handles like the .45 ACP Thompson models until you pull the trigger. Of course, on full auto, that’s still an experience even in .177 caliber.
Small details make the Umarex M1A1 an excellent CO2 model. Note the care taken to duplicate the safety and select fire controls, magazine release and markings with the lower frame group correctly marked: FULL AUTO/SINGLE and FIRE/SAFE. (WWII M1A1 photo courtesy Rock Island Auction Co.)

The operation of both guns is of similar design and both use the dual CO2 (back-to-back) system which makes the magazine into an air chamber once the seating screw and O-ring seal are tightened down. Both have a 30-round capacity and both use a reciprocating blowback action. The differences are in the respective designs, the folding metal stock on the MP40 and use of early plastics (Bakelite) for the pistol grip and foregrip of the original guns, vs. walnut on the M1A1, the charging handle for the MP40 being located on the left of the receiver, the M1A1 on the right, giving right- or left-handed users respective advantages for operation.

The charging handle rests forward when the gun is empty and the trigger has been pulled. After the magazine is inserted and the charging handle pulled, it rests further back exposing the top of the magazine. All of the warnings and manufacturer info is in small print on the underside of the triggerguard. The exposed white markings are the caliber, model, serial number, and ac proof.

It is fair to say that the new Umarex M1A1 benefited greatly from the development of the MP40 as a CO2 model in 2017, and at some point a head-to-head test will be done. But for now, let us fall into a new level of “BB gun mania” with the best WWII era CO2 airgun yet.

In Part 3 the first velocity and handling tests begin.

3 thoughts on “Umarex Thompson M1A1 Part 2

  1. I like the magazine CO2 system better than in the stock, less chance of breakage. 7.75 lbs on the weight is pretty close to the real deal. If they would add a wood stock(I would pay for it!) it would be very close to the original. Fire up “Roland the Headless Thompson Gunner” when you’re on the range with it!



  2. The Thompson if it works as well as the MP40, will leave the M1Carbine in the dust, despite the wood option of the Carbine. I have an M1 Carbine in 3o cal and was looking forward to the bb replica. I was surely disappointed. The Thompson appears to be of superior design and select fire function . The magazine was a weak point on the Carbine , which I understand has been upgraded . For me it makes more sense to go for the Thompson.


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