It’s time to go gansta’. It’s time to waste some Nazis. It’s time to introduce one of the original submachine guns – the Thompson Submachine Gun. Specifically, the M1928 (M1SB). This version of the Thompson is the US military version that was handed out to many US troops back in World War II.

Quick History

The Thompson submachine gun was made by John T. Thompson in 1918 during the end of the Great War. It is famous for being used by gangs during the 1920s – notably used by mob boss Al Capone.

Nicknamed the “Tommy Gun” during the Prohibition era.

There are two major versions of the Thompson submachine gun that are well known. The first version would be the classic rounded drum magazine with the front vertical grip that was popular with mobsters in pinstriped suits. The second version would be the military version that had a flat front handguard and straight box magazines used by US soldiers in World War II.

Firearm Overview

Before starting, it would be good to identify the main parts of the Thompson that are necessary for firearm operation.

Check out the images below for reference:

Thompson Breakdown

AR-15 Breakdown
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Standard wooden grip

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Activates the firing pin which fires the round.

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Magazine Catch/Release

Lever to catch and hold the magazine in place. Press down release the magazine from the weapon

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Back portion of the gun that provides support when shooting

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Rear Sight

Iron sights for aiming the weapon

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Bolt/Bolt Handle

Handle that loads and/or ejects a round from the magazine once pulled

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Ejection Port

Ejects the spent round from the firing chamber

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This version (M1) can hold 20 – 30 round stick magazines of .45 ACP

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Handgaurd & Barrel

Front hand rest to aim the weapon while the barrel sits on top

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Pivot Plate

Used for disassembly of the weapon

Once you have a good idea of where these important gun components are located on the weapon, you should know what is referred to in this “how-to” article.

Loading the Magazine

AR-15 Load Magazine
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The Thompson’s magazine is straight and the top lip is open pretty wide so loading those big .45 ACP rounds into it is actually pretty easy. Take the empty magazine with your off hand and a round with the other. Line up the round between the top of the magazine and push it down with your thumb. Keep doing this with each round of ammo until the magazine is completely filled. This type of Thompson magazines hold 20 to 30 rounds. The 20 round magazine is the most popular.

Load the Thompson

AR-15 Load Gun
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Putting the magazine in

Now that you have a fully loaded magazine, it’s time to load the Thompson with it. Pick up the Thompson with your good hand (careful, it’s heavy) by the grip.  If you need to, hold the stock between the pit of your arm to get a firm hold on the weapon. Take the magazine with the off hand and line up the magazine rails (back of the magazine) up with the guides right in front of the trigger from the bottom. Push the magazine up within the rails until you cannot push it up anymore.

Chambering a round

Once the magazine has reached the top and into place, take bolt handle, which is located on the right side of the weapon and pull it all the way back. The ejection port should be open and you should be able to see a round lining up into position. Let go of the bolt handle to close the bolt to chamber a round.

Be careful: You now have a locked and loaded submachine gun

Manage the Sights

AR-15 Manage Sights

Using Iron Sights

The Thompson has static iron sights which stay in position. You can look through the rear sight, which is usually a circular hole, and line up with the front sight. Make sure the top line of the front sight is in the middle of rear sight circle.

Firing the Thompson

AR-15 Fire Rifle

Line up your shot

Everything on the weapon should be good to go. It’s now to get into stance for firing the Thompson. We won’t be going into the many different stances for firing but we’ll use a common stance. Fighting Stance is an extremely used and effective stance for new and advanced shooters. I recommend using this form if this is your first time shooting a Thompson submachine gun.

Get into stance with your forward hand griping the front handguard and your back hand hold the pistol grip on the submachine gun. DO NOT PUT YOUR FINGER ON THE TRIGGER. Lean into the weapon and look down the sights to line up your shot.

Fighting Stance
Switch from Safe to Fire
Fighting Stance
Switch from Safe to Fire

It’s time to shoot. Switch the safety from safe to fire with your thumb. Now it is okay to put your index finger (or whatever finger you are comfortable firing with) and pull the trigger to fire at the target lined up in your sights. You will notice that with each shot, the shell casing will eject out of the ejector port. Please note that these shell casings are hot.

Once done firing, make sure you TAKE YOUR FINGER OFF THE TRIGGER and flip the safety back to safe whether you are out of ammo or not. This is always a safe practice for an firearm and not just the Thompson. Also, make sure to never point the gun in the direction of where you don’t want to shoot.

Reload the Thompson

AR-15 Reload Gun

The Thompson has a magazine release lever located right above the trigger. You can see that is it oddly shaped and covers the top of the trigger and connects right into the magazine guides in front of the trigger. Push up on magazine release lever for the catch to unlock. Slide the magazine out by pulling it down and out of the guides. Repeat the “Load the Thompson” section if you have a freshly loaded magazine. If you don’t have a loaded magazine, repeat the “Loading the Magazine” section and continue from there.

Manage a Jam

AR-15 Manage Sights

Since this is quite an old weapon, malfunctions and jams happen every now and then. Jams are usually pretty easy to handle but can be frustrating at times to remove the malfunctioning round and chamber a new one properly. The following is a basic tutorial fix a common failure-to-feed jam.

Hit Magazine Release and pull out magazine
Prepare fully loaded magazine
Insert new loaded magazine
Hit bolt release to chamber new round
Hit Magazine Release and pull out magazine
Prepare fully loaded magazine
Insert new loaded magazine
Hit bolt release to chamber new round

There could be multiple ways you could have a jam. This is one of the basic ways. Once your gun stops firing, but you know there is more ammo in the magazine, take a quick look around the weapon to see if there is anything wrong with it. NEVER LOOK DOWN THE BARREL OF A GUN.

Failure-to-Feed Fix

With jams like these, a round is usually stuck in the ejection port. Put the safety on to prevent anything from happening as you tend to the jam. Pull back the bolt handle and hold it back while you gently give the weapon a shake on the right side to get the malfunctioned round out of the feed. Once the round is out, let go of the bolt handle and try to get the gun to feed normally.

Checking it twice

I would recommend releasing the magazine and checking it to see if the ammo in the magazine looks to be feeding okay. Re-insert the magazine and make sure it is seated correctly. Make sure the magazine is up all the way to feed properly. Pull back the bolt handle once again to see if the gun feeds properly. If a round was already in the chamber, that one will eject and a new one will feed into the firing chamber. This should indicate that you are good to go.

Warning: Once again you now have a loaded weapon

Repeat this steps if the gun jams again. If it does this multiple times, you might need to clean your weapon.

This was a basic overview on how to shoot an Thompson Submachine Gun. This was a special article to feature a well know gun that has plenty of history. If you are brand new to firing guns, keep practicing. Many guns can be intimidating to new users so keep familiarizing yourself with new firearms so you can constantly get better. If you are looking to shoot an AR-15, check out that tutorial.

Remember, Practice Makes Proficient.