Mossberg 940 Pro Field: Shotgun Review

When I think of America, I think not of Starbucks, but rather of a Mossberg pump shotgun and a memorable day afield with friends and family seeking fun and food. Obviously, I’m not alone, because since 1961 the family-owned-and-operated firearm firm from North Haven, CT, has sold over 12 million Model 500s to rank-and-file hunters, home defenders, police forces and elite military units everywhere. Why? Because the venerable pump gun works every time, anywhere, yet costs under $500. But my stereotypical thoughts about Mossberg are evolving.

In 2020, Mossberg unveiled its 940 JM Pro semi-automatic competition shotgun designed by likely the best all-around shooter in history, Jerry Miculek. It’s a gun conceived to compete with the best gas-action semi-autos around, yet thanks to Mossberg’s well-oiled production line and its sales volume, the 940 is priced significantly less. In fall of 2021, it will introduce the 940 Pro Field, a 12-gauge, do-all semi-auto designed for hunters—especially waterfowlers. Although I didn’t have it for a fall where I could wave it at banking mallards, I had plenty of time to evaluate it this spring as I chased Gould’s turkeys in Mexico. A new Mossberg in Old Mexico, you ask? I’ll get to that later.

The 940 Pro Field Inside and Out

While the 940 has undergone a facelift, the real story is its internals that were redesigned to run more efficiently with a wider range of ammo. How? The gas delivery system features two oversized ports in the gas cylinder. A robust, short-stroke piston assembly accepts the burst of gas from the fired shell and slams rearward, moving the spacer tube, pusher assembly and the bolt assembly backward to cycle the action at similar speeds regardless of the load.

Another key to the 940’s enhanced reliability is owed to its innovative spacer tube. This 3.5-inch aluminum cylinder that rides on the mag tube features grooves to reduce surface area and to allow carbon fouling and moisture from condensation a place to go rather than just building friction under it. All critical internal parts are boron-nitride-coated to further reduce friction. Translated, the 940 is touted to run 1,500 rounds without cleaning compared to 500 for the 930.

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Externally, the 940 Pro Field features several key upgrades. Primarily, its plastic buttstock is adjustable via five spacers and shims that alter drop at comb/heel and cast on/off, as well as a modular buttpad system that makes the gun’s LOP adjustable from 13 inches to 14¼. These critical aspects of shotgun fit are imperative for intuitive shotgun shooting, recoil management and overall shooter satisfaction. Next, engineers slimmed the fore-end and made it flush-fitting to the receiver. Initial Pro Field models sport a 28-inch, vent-rib barrel with screw-in choke tubes.

The 940 JM Pro features oversized controls to reduce fumbling even while wearing gloves. The bolt release button also serves another nifty purpose; with the carrier manually depressed, a push will release a shell from the magazine tube so the mag can be emptied, or a single shell replaced for when a goose suddenly bombs the spread without cycling each shell through the chamber.

On the Range

I found the 940 came up to my eye naturally. Instantly, I hit fast flying targets without conscious thought, indicative of a gun that shoots where I look. This is thanks in large part to great stock fit and a well-regulated barrel. Furthermore, it’s silky to load owing to its forend contour, non-pinching loading port, and finger-friendly springs. Even including a break-in period, I could not get the gun to jam with 1 1/8th oz. loads and heavier.

The 940 delivered symmetrical patterns with Winchester DryLock Super Steel No. 2s with the gun’s modified choke tube. Although recoil with this 1,475 fps, 1 ½-oz. load is not what I’d call mild considering the gun’s 7.9-lb weight, it was milder than expected thanks to the 940’s gas system, recoil pad and return springs that are efficient recoil soakers. The receiver is drilled and tapped for an optic, and camo options are forthcoming.

Considering all the 940 Pro Field’s features combined with its reliability and blue-collar price tag, it would be at home in any duck blind…or in Mexico. You see, formerly when I thought of Mossberg I thought of America and pump shotguns. But now I’m reminded of that spring morning in old Mexico when I used Mossberg’s new, semi-auto to hammer a huge Gould’s gobbler.

Mossberg 940 Pro Field Specifications

• Type: Gas-operated semi-automatic shotgun
• Gauge: 12-gauge, 3”
• Magazine: 4 + 1
• Sights: Front Hi-Viz bead
• Stock: Synthetic; adjustable 13” -14 1/4”
• Weight: 7 lbs. 9 oz.
• Barrel Length: 28"
• Finish: Matte black
• Chokes: Interchangeable improved cylinder, modified, full
• Accessories: 3 choke-tubes, case, wrench, 5 shims, 4 spacers, 3 buttpad spacers
• Suggested Retail Price: $800