Tested: Inland Manufacturing M37 Trench Shotgun

posted on July 29, 2016

Founded in 2013, Inland Manufacturing is a company dedicated to producing faithful replicas of World War II-era firearms here in the United States. The company's first offerings included G.I.- type 1911 pistols and several versions of the M1 Carbine. New for 2016, Inland is offering a replica of the 12-ga. Ithaca Model 37 "trench gun" (or riot gun) shotgun. 

I had an opportunity to meet with Ron Norton, president of Inland Manufacturing, to learn more about what precipitated the release of this shotgun. He said several factors played a role. The company had plans to provide World War II re-enactors and those who wish to participate in period 3-gun competitions with a complete set of firearms, so a shotgun was needed to round out the pistol and rifle offerings. Their research confirmed that the Ithaca Model 37 was one of the most highly sought after models of the era because of its reliability and smooth operation. Since it has been out of production for over 40 years, an historically accurate replica would be of real interest to collectors as well as re-enactors. 

To ensure the authenticity, quality and reliability of its new M37, Inland teamed up with the Ithaca Gun Company, whose headquarters are just 80 miles away from the Inland plant. As a result, the M37 looks right, runs nicely and is 100 percent American made.

The new M37 is a manually operated pump-action 12-ga. shotgun with a 3" chamber. Despite its vintage appearance, this shotgun is manufactured using modern materials and up-to-date manufacturing techniques. This means the M37 can safely fire shotgun shells loaded to standard, high velocity and magnum pressure levels with payloads including birdshot, buckshot and slugs. 

The shotgun is made entirely from carbon steel treated with a matte-black Parkerized finish. The only piece of polymer to be found is the black butt plate attached to the shoulder stock. The 20" barrel features a fixed-cylinder bore choke and a bead-type front sight. Clamped to the muzzle is the distictive M1917 Bayonet lug, with an integral shoulder sling loop, which also supports a 12" long ventilated heat shield, or handguard if you prefer. The tubular magazine located below the barrel accepts up to four 12-ga. shells for a total of five shots with one in the chamber. 

The sliding fore-end is fitted with a rounded and grooved walnut grip with a plain non-reflective oil finish. Most current production shotguns have slides fitted with a left- and right-side extension to engage the bolt assembly. But true to form, the M37 has only the left-side extension.

The steel receiver follows the Browning Model 17 design, which means it does not have the right-side ejection port found on Remington, Winchester and Mossberg shotguns. Instead, spent shell casings are ejected downward out of the loading port. This feature gives the shotgun a tactical advantage in that it does not advertise the operator's location by flinging spent shells sideways into the air. It also means shooting companions standing to the right won't need to dodge flying hulls. The top of the receiver is grooved to reduce glare.

The rounded trigger guard is a combat-ready steel model that can certainly handle more abuse than the less durable polymer guards commonly found on sporting shotguns these days. The slide release rests along the right side of the trigger guard with the cross-bolt safety located behind the trigger. It's interesting to note that the safety has an exposed detent on the left side which is something you don't see in newer models. 

The trigger is a smooth-faced steel bow with a refined feel that can easily compete with the best tuned 1911 triggers on the market. It was exceptionally smooth with no take-up and a very short arch of travel (0.02" according to my digital calipers). The trigger broke cleanly with 4 lbs. 7 oz. of trigger pull. It should be noted here that the trigger mechanism of the M37 will not allow the gun to “slam fire.” The original Ithaca 37 allowed the operator to hold the trigger down causing the shotgun to fire as each round was “slammed” into the chamber. This means the gun would fire as fast as the solider could work the slide. The Inland M37 requires the trigger to be cycled for each shot and will not fire if the trigger is held down as a round is chambered.

The smooth, unembellished solid-walnut shoulder stock has a traditional pistol grip and is tightly fitted to the receiver. The polymer butt plate is partially serrated and held in place by two screws. A second steel sling mount is located near the butt plate.

I put the M37 through its paces at the shooting range with a mix of low and high brass in 2¾" and 3" 12-ga. shotgun shells. I soon learned that under this shotgun's gruff combat exterior was a precision-machined mechanism that would be at home in a top-notch competition gun. Everything about its operation was smooth and comfortable to work with. The movement of the slide, the interior of the loading port, the trigger, and the loading and ejection of ammunition: it was all buttery smooth.

The M37 was also reliable. I had no ammunition related or mechanical problems in the course of testing. The shotgun was patterned with four different loads. It was fired from a standing position into OPSGEAR RED Silhouette paper targets set at 7 yards from the muzzle. 

Aguila's 2¾” Standard Velocity Sporting Clays low brass shell, loaded with 11/8 oz. of 7½ Birdshot launched at 1225 fps. produced a moderate level of felt recoil and formed the largest pattern of the test with a spread of 10.00".

Federal Premium offers a devastating 3" high brass Magnum load stuffed with 41 pellets of #4 Buckshot that fly along at 1100 fps. I always bear down and get ready for the recoil produced by this shell but it still rocks me back each time. The #4 buckshot spread out to form an 8.50" pattern.

Hornady's Critical Defense 2¾" high brass round is loaded with 8 pellets of 00 Buckshot to a velocity of 1600 fps. It had a more manageable level of felt recoil and formed the tightest group of the test with a pattern of just 2.50".

The last round was Winchester's hybrid PDX1 Defender 2¾" high brass round. This shell launches a single 1-oz. rifled lead slug followed by three pieces of copper-plated 00 buckshot at 1150 fps. This target is a little harder to read because of multiple impacts from the fracturing wad. The slug formed the center of a 3.75" pattern with the three 00 buckshot pellets striking at the 12-, 6- and 9-O'clock positions.

Inland Manufacturing's new M37 Trench Shotgun, built in conjunction with Ithaca Gun Manufacturing, is a faithful replica of an iconic shotgun that collectors and shooting enthusiasts can both enjoy. Like other Inland offerings, this shotgun exhibits meticulous attention to detail while providing a high level of quality and reliability. Take the M37 out for a spin on the WWII re-enactment shooting circuit or stage it as a home-defense gun, it can easily serve in either capacity.

NRA Specifications
Manufacturer: Inland Manufacturing
Action: Manual Pump Action, Bottom Loading and Ejection
Caliber: 12 gauge
Chamber: 3"
Finish: Matte Black Parkerized
Fore-end: Oil Finished Walnut
Shoulder Stocks: Oil Finished Walnut with Polymer Butt Plate
Barrel Heat Shield: Yes
Bayonet Lug: M1917 Bayonet
Choke: Fixed Cylinder Bore (.730")
Safety: Cross Bar
Front Sight: Bead
Rear Sight: None
Barrel Length: 20.00"
Overall Length: 38.50"
Length of Pull (LOP): 14.00"
Trigger Pull: 4 lbs. 7 oz.
Weight: 6.70 lbs.
2¾" Shell Capacity: 4+1
3" Shell Capacity: 4+1
Accessories: Owner's Manual
MSRP: $1259


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