Optic-Ready Multicam Mossberg 940 JM Pro Review [w/Video]

Estimated reading time: 10 minutes

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Back in January 2020, the 940 JM Pro autoloading shotgun hit the scene, shaking up competitive shooting with its slick design and ready-to-roll features. Teaming up with champ shooter Jerry Miculek, Mossberg just improved upon these 12-gauge beasts by including optic-ready models in the existing lineup. This model features the Shield RMSc footprint so you can slap on those micro dot sights with ease. Also, setting this 12-gauge, 3-inch competition autoloader apart is its black anodized receiver and complementing Multicam Black camo stock and forend.

Mossberg 940 JM Pro Specifications:

• Gauge: 12 Gauge
• Action Type: Semi-Auto
• Chamber Size: 3″
• Usage: Competition
• Barrel Type: Vent Rib
• Barrel Length: 24″
• Barrel Finish: Matte Blue
• Capacity: 9+1
• Length: 44.75″
• LOP: 13″-14.25″
• Sights: Front FO; Optic-Ready
• Stock: Adj. LOP, Cast, Drop – Synthetic (Black Multicam)
• Weight: 7.75

Upgrades

Now, let’s talk upgrades. Building upon the trusty Mossberg 930, the 940 JM Pro steps it up with a gas system that keeps chugging for up to 1,500 rounds before needing a scrub. It breezes through both 2.75 and 3-inch factory-made ammo, even if it’s packing a solid 1 oz or more. Plus, Mossberg has coated the insides – the gas piston, magazine tube, hammer, and sear – with nickel boron for extra rust resistance and a smooth ride. Also, the receiver is sporting an anodized finish. 

940 JM Pro Out of the Box

The 940 JM Pro is shipped in a cardboard box and includes stock extensions, Briley extended choke tubes, extra fiber optic front inserts, an owner’s manual, a gun lock, and some stickers. This shotgun is shipped with a cover plate installed for those who will not mount a red dot.  

Sights

When it comes to shotgun sights, I am a big fan of the HIVIZ TriComp front fiber optic chosen for the 940 JM Pro. It provides great contrast and is quick to find. Mossberg even included interchangeable LitePipes for those who prefer a color different than green or need to replace one down the road. 

While the 940 JM Pro has been out for a little while now, this optic-ready variant is new as of early 2024. The receiver has a Shield RMSc footprint machined directly into it, and a cover plate is included from the factory. Red dots have taken over the rifle and pistol scene, and they are now creeping into the shotgun world as well. While running a red dot on a scattergun is new to me, I thoroughly enjoyed testing this paired with a Holosun SCS Carry. 

One issue I ran into was that not all red dots made for a Shield RMSc cut will work with the 940 JM Pro. Specifically, I couldn’t mount the Vortex Defender-CCW. It was slightly too long and the back of the housing hit the angled cut on the receiver. I am not sure if this was a red dot problem or an optic cut problem, but an Sig ROMEOZero elite fit without an issue so I was 2/3. Also, the screws that came with the Holoson SCS Carry were too long. The left screw worked just fine, but the right one stuck through the top of the receiver and hit the bolt, keeping the shotgun from cycling.

Furniture

This new variant of the 940 JM Pro also features Multicam Black camo for both the stock and forend. While looking great, the grip of the synthetic stock and forend also feature Mossberg’s mildly aggressive texturing. It’s enough to maintain a solid non-slip grip, yet not as rough as some combat shotguns. Built for 3-gun competitions, I would have liked it to be slightly more aggressive, but it still does the job well. 

Controls On the 940 JM Pro

Built for competition, the 940 JM Pro features an enlarged loading port designed for quad loading. Loading was quick and easy, and the follower wasn’t pinching my finger like many shotguns do. There is plenty of access, and this enlarged port is comparable to a magwell on a pistol except its flush with the bottom of the receiver. 

Additionally, this shotgun is equipped with an enlarged bolt catch, simplifying reloads especially when loading from a shell card. Throughout this review, I mounted the Esstac 7 round card using their adhesive strip, and it held securely in place. This setup provided convenient access to additional ammunition. The enlarged bolt catch proved effortless to engage after chambering a round, facilitating quick follow-up shots.

Trigger

When it comes to shotgun triggers, most people don’t talk about them. However, the 940 JM Pro’s trigger is worth talking about. The slack is short, and the wall is well-defined. When pulling past, there is a bit of creep before the trigger breaks, but it’s not bad. I measured the pull weight to be between 3.5-4lbs, but after the break, the reset is amazing. It is extremely short and places your finger right back on the wall ready for that next shot. When it comes to competition guns, having a trigger like this is essential.

Patterning 

A useful addition to this shotgun is the Briley extended choke tubes. An Improved Cylinder, Cylinder, and Modified all engraved with constriction are all included. This makes it easy to tell which one is currently installed and gives users options right out of the box. 

Aiming to see how this shotgun patterns, I shot a cardboard target from 10 yards. I did this using the Modified Briley choke with 2 3/4″ #7 1/2 shot Fiocchi. I got about a 5.5″ diameter group, or roughly 55 MOA.

Throughout this review, I was able to put a couple hundred rounds through the Mossberg 940 JM Pro. Most of the ammunition used was 2 3/4″ #7 1/2 shot Fiocchi which you can find at Ammuntiontogo.com. They are the official ammo sponsor for this shotgun review and offer a wide selection of competitively priced ammunition. They have quick shipping, an easy-to-use online website, and competitive prices. Go check them out! 

940 Jm Pro Performance

Having been a proud owner of the 930 JM Pro for quite some time, I must say, this newly upgraded multicam/optic-ready model has exceeded my expectations. From the moment I unboxed it, this shotgun has been incredibly impressive. I’ve put it through its paces, firing a couple hundred rounds of mostly birdshot, with a mix of slugs and 3″ magnum coyote rounds thrown in. Never once did it falter, all without a single cleaning session. Thanks to its robust new gas system, nickel boron-coated internals, and competition-grade loading port, elevator, and follower, every aspect of its performance has been consistently smooth and reliable throughout my entire experience with it.

Also, this shotgun cycles fast. I used the 9+1 capacity to dump 10 rounds into a steel target at 10 yards in just 1.75 seconds. Some semi-auto shotguns are sluggish, but the 940 JM Pro runs quickly and smoothly. When paired with a red dot, I consistently hit steel from 100 yards using 1oz slugs. For those who want to see it in action, I posted a video to my Instagram page below: 

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I also spent an afternoon shooting one of the 12 stand sporting clays courses at Texas Gun Ranch with some of my buddies. We took turns using this shotgun to put extra rounds through it, and it decimated clays without an issue all day long. 

Summary

This shotgun performed exceptionally well throughout my testing and incorporates many impressive features. Standing out in the realm of 12-gauge, 3-inch competition shotguns is its sleek black anodized receiver and Multicam Black camo stock and forend. While the inclusion of the HIVIZ TriComp front fiber optic sight adds a nice touch, the real standout is the Shield RMSc footprint, which allows for easy mounting of a red dot sight.

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Additionally, it comes equipped with a set of Briley extended choke tubes (Improved Cylinder, Cylinder, and Modified) and an extended magazine tube, boosting capacity to 9+1 rounds. Priced with an MSRP of $1,240 and a street price closer to $1050, the Mossberg 940 JM Pro offers exceptional value for those seeking a reliable 3-gun shotgun. I would highly recommend for anyone in the market for such a firearm.

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