The Auto-Ordnance Thompson Carbine — Americana at its Finest

One of the most famous icons among American firearms is the Thompson submachine gun (SMG). Originally developed as a trench broom for use during the horrific battles of World War I, the Thompson was not fully developed until 1921, missing the Great War. However, it saw widespread use in America. Admittedly, both sides heavily used the Thompson SMG—with lines often blurred—during the Prohibition Era.

Thompson submachine gun with brown wood-grain accents, pointed to the right, lying on brownish gray wooden planks.

The concept of the Thompson SMG dates back to the Thompson LaGarde tests which determined a military handgun needed to be a .45 caliber. Not news to men of experience; the results were unassailable, which led to the United States adopting the Colt 1911 .45—the same cartridge used by the famous Thompson SMG.

The History of the Thompson SMG

Thompson spent a good portion of his military career attempting to convince the Army as to the superiority of fully-automatic weapons for military use. He was unsuccessful as far as shoulder-fired weapons were concerned. We went to war with the Springfield 1903A3, a fine rifle sporting a magazine cut off for single shot use to conserve ammunition.

Thompson retired from the military and spent most of World War I managing the successful war effort at Remington Arms Corporation. At the time, the Eddystone factory Thompson managed was the largest in the world. Thompson developed the fully-automatic Trench Broom largely on his own time and his own dime—although he did have financial backers and partners in stock holdings. Thompson felt the long recoil system with a recoiling barrel was too complicated, and the gas system was unreliable or subject to problems in most arms of the day.

Fortunately he was able to use the Blish lock, invented by a Naval gunnery officer, in the straight blowback Thompson SMG. Blish took a share in stock for the use of his patent. The Auto-Ordnance Corporation was formed and their original product, largely built by outside contractors, was originally called the Annihilator. The Auto-Ordnance board elected to change the name to the Thompson and invented the phrase “submachine gun.” The Thompson was demonstrated at CampPerry in 1920 to the astonishment of all who observed the fast firing gun. With military sales in limbo, Auto-Ordnance marketed the SMG to police and corrections officials. At the same time, Auto-Ordnance contracted with Colt to produce about 15,000 Thompson SMGs.

Next came the Volstead act and Prohibition. The Thompson was used by rumrunners and mobsters, primarily against one another, but also against peace officers. Tightened up sales policies resulted in less Thompsons in the hands of thugs and an underworld price of several thousand dollars. At the time, the Thompson sold for around $275 to legitimate buyers. In comparison, the Winchester 1907 .351 self-loading rifle sold for less than $50.

The Thompson was obtained by the United States Coast Guard. This watershed event led to the Thompson being obtained the U.S. Marine Corps. The Thompson saw action in Nicaragua and won high praise from the Leathernecks. The armed services asked for, and got, the M1928A1. The significant difference was that the rate of fire was reduced from 1200 rounds per minute (rpm) to a more manageable 600 rpm. The old style vertical foregrip was changed to the horizontal style. The U.S. Army finally began purchasing Thompson SMGs in 1932, after it adoped the M1928A1.

100 round drum in dark gray against a light oak woodgrained background.

Auto-Ordnance struggled through these years with the bulk of the original Colt contract SMGs still on hand. Then events in Europe supercharged sales. The French ordered 3,000 units in 1939. Britain and the United States obtained what would be virtually open-ended contracts. These wartime Thompsons were produced by Savage. Auto-Ordnance also produced receivers—upper and lower—and other parts were delivered to Bridgeport by contractors. During 1942 , the company marked the production of a half-million Thompson M1A1 model submachine guns for the war effort. During this period, several modifications were instituted.

  • The barrel fins were deleted.
  • They were not as finely finished.
  • The Blish lock was deleted and the Thompsons worked just fine.
  • The cocking handle was moved to the side of the receiver.
  • There was no longer a cut for the 50 or 100 round drum magazine, only stick magazines were used.

While different, these were workmanlike and effective tools. The Thompson served from World War II to Korea and Vietnam and is still seen in conflicts world wide. While it is possible to own a Thompson in most states, if you are willing to go through the legal hoops, the Thompson costs about the same as a new truck.

Today there is an affordable alternative. Auto-Ordnance Corporation produces a semi automatic version of the Thompson. The current company with rights to the name Auto-Ordnance is a branch of Kahr Arms. The .45 caliber carbine isn’t any more expensive than a good AR-15 rifle, although the modern .45 carbine has a longer barrel for legal reasons. Once you get accustomed to the 16-inch barrel versus the original 10.5-inch barrel, the modern Thompson is a very nice looking firearm. The cocking lever is on the top of the receiver in 1928 model fashion, and the Blish lock is deleted. The barrel fins are intact, and so is a near copy of the Cutts Compensator. Best of all, there is a quality reproduction of the original Lyman adjustable sight. This is a large, heavy firearm true to the looks of the original, well-made of good material, and a quality piece of Americana well worth its price.

Features of the Thomson SMG

Thompson semi-automatic .45 caliber with the emphasis on the controls, lying on brownish-gray planks.

The Thompson illustrated was purchased complete with a stick magazine, hard case and 100-round magazine. Fit and finish are good and the wood-to-metal fits well. Overall, the piece seems to be of good quality. Firing the Thompson meant learning to work the bolt efficiently since it is a very heavy bolt with a powerful recoil spring. I recommend some practice in bracing the butt stock when cocking the bolt.

It is best to cock the bolt on an empty magazine and leave it open and locked. Then perform the following steps.

  1. Remove the magazine.
  2. Load the magazine.
  3. Reinsert the magazine.
  4. Release the bolt.

The 100-round drum demands some labor to make ready. The cartridges are arranged within the drum magazine in neat rows, and the magazine cover replaced. The key that opens the drum is used to crank the magazine spring by turning the crank some 15 clicks. One-hundred rounds is a lot of ammunition in a semi automatic carbine. The drum is heavy and the package is not one I would wish to drag around on patrol. As a perimeter defense firearm or for a prison or courthouse guard the Thompson has merit. The magazine release is held as you insert the magazine. The drum is inserted from the left side until it clicks into place. A neat little sheet metal block—known as the third hand—holds the magazine release open as the drum is inserted.

There was sometimes confusion in training, particularly at night, and the Thompson magazine was at times dumped inadvertently. It was said to be difficult to insert in the dark. I can see this, and if you contemplate using this piece for personal or home defense, be familiar with it. After my experience with this particular carbine, I can recommend the Thompson as a home defense tool or even for use by police agencies wishing to equip offices with a pistol caliber carbine. It is big and heavy, recoil is light and the piece is more accurate than most would realize. Of course, 99% of the purchasers will purchase the Thompson for pride of ownership and recreational shooting. I know several folks who own examples they have not fired; it is that type of firearm.

Testing the Thompson SMG

I spent a good amount of time getting used to the Thompson’s eight-pound trigger. While the Thompson is heavy, at over 10 pounds, steadying the trigger was a challenge with some nine pounds of compression. I spent long intervals in dry fire to master the trigger. The sights feature a simple V notch rear when folded down. When folded up for long-range fire there is an aperture sight. The V-notch rear sight is capable of producing good accuracy at modest range. After some acclimation, the Thompson produced four-inch 100-yard groups for five shots at 100 yards. I have fired the occasional three-inch group and also suffered very poor results with certain economy loads. With quality ammunition, the Thompson is accurate enough for its intended task; it is about as accurate as the average M1 .30 carbine or AK-47 rifle. It is much heavier and—as range increased—the drop of the .45 ACP cartridge became obvious.


Two submachine guns in black with brown woodgrain accents, one above the other, lying on brownish gray wood planks.

The Thompson fed hollow point bullets, which was a little surprising. Overall, the straight-line feed produced good results. There is a velocity increase over the pistol, although it depends on the powder charge and bullet used. In handloading, medium burning powder produced ejection port flash and erratic results in this blowback firearm. Fast burning powder is best. A 230-grain load, producing 800 fps in a pistol, clocks perhaps 920 fps in the Thompson. The Cor-Bon 185-grain JHP clocks 1150 fps from a pistol, and a blistering 1500 fps from the Thompson’s 16-inch barrel—a useable increase. With a combination of greater practical accuracy, low recoil and increased wound potential, you can see that the Thompson maximizes the .45 ACP cartridge. While perhaps an odd combination for any type of game, the Thompson moves standard .45 ACP loads into .460 Rowland category. I found the ballistics fascinating and spent quite a bit of time on the range with the Thompson. There were no failures of any type to feed chamber fire or eject. This is a good reliable carbine with many good features.

I also ran a number of combat drills with the Thompson. The piece comes to the shoulder quickly and easily and once on target tends to stay there. Using the V-notch rear sight and firing as quickly as possible, the Thompson and I produced tight groups on man-sized targets to 50 yards. It was possible to ring the eight-inch steel gong at 100 yards on demand when using the aperture sight and paying attention to the trigger. I did not use the 100-round drum during this test; it is simply too much like lifting a barbell. Thirty rounds seems adequate for any likely emergency.

The Thompson carbine is a wonderful piece of history, affordable in comparison to the original and well made of good material. This is a firearm steeped in history and well worth your attention.

Accuracy results

Load 5-Shot Group at 100 yards
Cor Bon 230-grain Performance Match 3.5 inches
Cor Bon 230-grain JHP 4.0 inches
Cor Bon 185-grain JHP 4.5 inches
Fiocchi 230-grain FMJ 4.65 inches
Fiocchi 230-grain JHP 3.8 inches
Fiocchi 230-grain XTP 3.65 inches
CCI Speer Blazer 230-grain FMJ 4.9 inches
Speer Lawman 230-grain FMJ 4.0 inches


Load Velocity Group Size
200-grain Magnus SWC/WW 231 1180 fps 4.25 inches
200-grain Speer Gold Dot/WW 231 1221 fps 4.0 inches

The Auto-Ordnance 1911A1

I would be remiss not to mention the 1911A1 pistol offered by Auto-Ordnance (AO). These days everyone, including Fred and Mabel’s machine shop, seems capable of putting together a 1911, although few are firearms I would bet my life on. All who fired the AO gun commented they would buy American in this case, and chose the AO 1911A1 pistol. All quality handguns do better with one load more than the other, but the Auto-Ordnance is consistently accurate with a variety of loadings.

Dark gray Thompson SMG with emphasis on engraved name with the words "Auto-Ordnance Corporation, WOrcester, Massachuetts, U.S.A" lying on brownish-gray planks.

Remember, lubricate the pistol well and use hardball for the break in period. True to the 1911 standard, the Auto-Ordnance required a 100 round break-in with full-power ammunition, although not all 1911 pistols require a break-in period. Just the same, perhaps the Auto-Ordnance is built the old way? Once these failures to fully go into battery were out of the way—with full power ball ammunition for reference—this 1911 never stuttered and gave good accuracy. This is a straight up rendition of the pistol that won World War II. (Well, maybe the B-29 and the atom bomb had something to do with it as well.)

There is nothing wrong with a standard 1911 for personal defense or general use; there is nothing extraneous about this pistol. If you want to own a good GI pistol, the Auto-Ordnance 1911A1 looks right, feels right, stirs the emotions, and is the right price. However, it is more accurate than a GI gun and feeds hollow points.

Kind of a sleeper.

What Americana gun gets you excited? Have you fired a Thomson SMG? Share your experiences in the comment section.


About the Author:

Bob Campbell

Bob Campbell’s primary qualification is a lifelong love of firearms, writing, and scholarship. He holds a degree in Criminal Justice but is an autodidact in matters important to his readers. Campbell considers unarmed skills the first line of defense and the handgun the last resort. (He gets it honest- his uncle Jerry Campbell is in the Boxer’s Hall of Fame.)

Campbell has authored well over 6,000 articles columns and reviews and fourteen books for major publishers including Gun Digest, Skyhorse and Paladin Press. Campbell served as a peace officer and security professional and has made hundreds of arrests and been injured on the job more than once.

He has written curriculum on the university level, served as a lead missionary, and is desperately in love with Joyce. He is training his grandchildren not to be snowflakes. At an age when many are thinking of retirement, Bob is working a 60-hour week and awaits being taken up in a whirlwind many years in the future.

Published in
Black Belt Magazine
Combat Handguns
Rifle Magazine
Gun Digest
Gun World
Tactical World
SWAT Magazine
American Gunsmith
Gun Tests Magazine
Women and Guns
The Journal Voice of American Law Enforcement
Police Magazine
Law Enforcement Technology
The Firearms Instructor
Tactical World
Concealed Carry Magazine
Concealed Carry Handguns

Books published

Holsters for Combat and Concealed Carry
The 1911 Automatic Pistol
The Handgun in Personal Defense
The Illustrated Guide to Handgun Skills
The Hunter and the Hunted
The Gun Digest Book of Personal Defense
The Gun Digest Book of the 1911
The Gun Digest Book of the 1911 second edition
Dealing with the Great Ammunition Shortage
Commando Gunsmithing
The Ultimate Book of Gunfighting
Preppers Guide to Rifles
Preppers Guide to Shotguns
The Accurate Handgun
The Mission of Cheaper Than Dirt!'s blog, The Shooter's Log, is to provide information—not opinions—to our customers and the shooting community. We want you, our readers, to be able to make informed decisions. The information provided here does not represent the views of Cheaper Than Dirt!

Comments (8)

  1. Jim,
    I had the same uncontrolabilty problem while shooting two M-60 Machineguns while standing unsupported like Rambo. It was a hoot but no matter how many times I did it I didnt get any better.

  2. My dad flew in bombers in WW2, and carried a Thompson while guarding the planes. He said they were tough to fight the rise when firing two of them at simultaneously, but still fun.

  3. I have a Korean War. He carried a Thompson and said he cussed it every time he had to carry it and its ammo around. But he said when the NK’s and Chicoms attacked and he cut down on them with the gun, no one stuck their heads up to see who or where the shots were coming from. He said he credits the Thompson for getting him through the war.

    BTW I remember reading that the navy turned down the Thompson because of its high rate of fire (1200 rpm).

  4. I purchased a TM1 last year. I had to send it back for readjustments, which seems like the norm for the modern Auto Ordnance. Before it was sent back it was worthless and could not cycle rounds almost at all. After it came back, however, it runs like a clock, and is quite reliable.

    For all its positive points, its accuracy is the most astounding. It does fire close groups for a pistol carbine, far surpassing any expectations I had for it. Yes, standard 230’s will drop like a stone, but once you figure the drop and learn to adjust, or rather get the proper sight, you can hit targets at 100 yards with astounding accuracy and consistency. Good enough to slam raccoons and skunks for sure, about the only game and the furthest ranges that this rifle really could be practically used for in hunting. The extra heat from the longer barrel is apparent, giving the already hard hitting 45acp a little extra pepper.

    As for close quarters, I’m not sure what to say. I’m of the ultra old school, take enough firepower to kill a man in one shot, I’ll stick to my 308 battle rifles at point blank ranges even. But as far as self defense pistol carbines, it has its shares of advantages and drawbacks. It is extremely heavy, which I like, but most people don’t. Worse, the kind of people who would refuse a full rifle and take a pistol carbine instead due to physical problems or weakness would possibly turn this away for being far to heavy, and at 36 inches as long as many 223 carbines. On the plus side, the extreme weight for caliber makes it an easy gun to master and control with quick shots once you get the rythem. As far as pistol carbines go, 45acp is high on the list for stopping power, and the Thompson’s handle them with authority. With 230 hp that feed reliably, even a novice could find this an easy weapon to hit a target multiple times with excellent control, and with more power and bigger bullets than 40 or 9mm.

    This is one hell of a fun gun. With the rise of rifle carbines, the pistol carbine sometimes loses its luster to many people for practical hunting and self defense. But on that note, guns like the Thompson are fun, easy to shoot, are not intimidating to shooters, and with shooting characteristics of a big 22 lr. You get a gun with almost no recoil, with the bolt kicking the gun more than the round, very little noise and blast, and a very comfortable experience. Add on interchangable ammo with your pistol, a real winner. Nearing 100 years old, this design shows its age compared to newer guns, and the category is facing obsolescence, but its a great conversation piece, a historical piece, and a tight shooting hard hitter in its category.

    Just don’t be surprised if you have to send it back right away.

  5. OH Yes…In my opinion it’s still the best of the best ,for C.Q.C. With a 50 Rd. Drum you would be hard pressed to find a better weapon, & I’m talking about the real deal,Safe Semi, Full..Take the stock off, and it would be very hard for anyone to see what you have hidden! And hey we are talking about a .45 A.C.P., and if hit in the hand you are going down. The one that I have shot is of older models, and the cycle rate was +/- 1100, Rds Min.. I, would love to have one, but the cost is over the top. I have seen them for $28,000.00 -$35,000.00…can’t do that, but if I, could I would. And if you are lucky enough , do yourself a favor ,and shot this typewriter.It will forever change your mind what C.Q.B. Weapon should be, and this baby has been around along time. Note: Also the one I shot was of closed bolt, and not open bolt, so as you know it was very old, but very bold. What a rush….G.W.O.

  6. I, too, have a ’27A1 (pre-Kahr) and agree wholly with all. But, I still have it… and am VERY jealous that you’ve put fire down range! Ditto on the Lotto!! }:o)

  7. I have owned a Thompson 1928A1 carbine and fired both stick and drum mags with it. It was a cool item to have in the safe, but it was not really practical for home defense and not powerful enough for the rifle range. I considered it a fun toy, but that was not enough of a reason to keep it, so I sold it. I have also had the privilege of firing a “real” Thompson SMG, and it is one of the highlights of all the firearms I have fired. Light on recoil and fast rate of fire, I would hate to have faced one in combat. The full auto Thompson would be high on my bucket list after I win the lotto, LOL.

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