Mossberg 940 Pro Tactical SPX — 12 Gauge, 18.5 in Barrel

Description

The Mossberg 940 Pro Tactical SPX — 12 Gauge, 18.5 in Barrel is a factory-built autoloader that ships with a Holosun 407K micro-dot, an M-LOK forend with integrated heat shield, and an adjustable synthetic tactical stock. It comes chambered in 12 Gauge with a 3-inch chamber and oversized controls for rapid operation. This is a ready-to-run security and duty shotgun designed for shooters who demand reliability and modularity without aftermarket guesswork.

Manufacturer	Mossberg
Model	940 Pro Tactical SPX
Material	Aluminum receiver, synthetic stock and forend
Compatibility	12 Gauge, 2.75- and 3-inch shells
Finish	Matte black anodized receiver, black synthetic
Weight	7.5 lbs (per manufacturer specs)
Condition	New

Key Features

• Optic-Ready with Holosun 407K Included — Why it matters: You get a proven micro-dot factory-mounted on an RMR-cut receiver, eliminating the need to buy or install a separate sight. The 407K gives you a crisp 6 MOA dot for fast target acquisition in low-light or high-stress situations.
• M-LOK Forend with Integrated Heat Shield — Why it matters: The M-LOK slots let you mount lights, lasers, or grips without extra adapters. The heat shield keeps your support hand cool during extended strings of fire, especially with slugs or buckshot.
• Adjustable Synthetic Tactical Stock — Why it matters: The stock adjusts for length of pull and comb height, so you can dial in fit for body armor, winter gear, or a natural cheek weld. A proper fit means faster follow-up shots and better recoil management.
• Oversized Controls and Six-Shell Carrier — Why it matters: The enlarged bolt release, safety, and charging handle work with gloved hands. The six-shell carrier gives you two extra rounds on the gun compared to standard four-shell carriers, reducing reload frequency during drills or defense.
• Gas-Operated System with Clean-Action Piston — Why it matters: The self-cleaning piston cycles a wide range of loads from light target shells to heavy 3-inch magnums without manual gas adjustment. This reduces fouling buildup and keeps the gun running longer between cleanings.

Who It’s For

This shotgun is for security professionals, duty officers, and serious home defenders who want a semi-auto that works out of the box with a dot and rail system. It also suits competitive shooters in 3-Gun or tactical shotgun matches who need a reliable, low-maintenance platform. If you prefer a pump or want a shorter barrel for transport, you might look elsewhere — this is a 18.5-inch barreled autoloader built for speed and accessory mounting.

Pros / Cons

• Pro: Ships with a Holosun 407K — no extra cost or installation hassle.
• Pro: M-LOK forend with heat shield means you can run a light and foregrip without burning your hand.
• Pro: Adjustable stock fits a variety of shooters and gear setups.
• Con: The 18.5-inch barrel is fixed and not threaded for chokes, so it’s limited to cylinder bore patterns — fine for defense but not for hunting or long-range slug accuracy.

Comparison

Feature	Mossberg 940 Pro Tactical SPX	Beretta 1301 Tactical	Remington 870 (Pump)
Action	Semi-auto, gas-operated	Semi-auto, gas-operated	Pump-action
Optic Ready	Yes, Holosun 407K included	Yes, but optic not included	No (requires gunsmithing)
Forend	M-LOK with heat shield	M-LOK, no heat shield	Standard synthetic
Stock	Adjustable LOP and comb	Fixed length of pull	Fixed or aftermarket
Capacity	6+1 (factory)	7+1 (factory)	4+1 (factory)
Price	$1109.10	$1450–$1600	$450–$600

FAQ

What loads does the Mossberg 940 Pro Tactical SPX cycle reliably?

Per Mossberg specs, the 940 Pro Tactical SPX cycles 2.75- and 3-inch shells from light target loads (1200+ fps) to heavy magnum buckshot and slugs. The self-cleaning gas piston handles the range without manual adjustment. Stick to quality factory ammunition for best reliability.

Can I mount a different optic on the 940 Pro Tactical SPX?

Yes. The receiver uses a standard RMR footprint, so you can swap the included Holosun 407K for any RMR-pattern micro-dot from brands like Trijicon, Holosun, or Shield. The factory mounting plate is included, and installation is simple with a Torx driver.

Does the heat shield affect barrel removal or cleaning?

No. The heat shield is integrated into the M-LOK forend, not the barrel. You can remove the forend for cleaning by loosening the forend nut (standard Mossberg tool). The barrel comes off separately after removing the magazine cap.

Is the stock adjustable for left-handed shooters?

The stock adjusts for length of pull and comb height, but the shotgun is configured for right-handed ejection. Left-handed shooters should expect brass to eject across the body. The safety is reversible, but the bolt release and charging handle are right-side only.

What is the warranty on the Mossberg 940 Pro Tactical SPX?

Mossberg offers a limited lifetime warranty to the original owner against defects in materials and workmanship. The Holosun 407K has its own separate warranty (typically 5 years). Register your purchase on Mossberg’s site for warranty coverage.

Ready to order?

• ✔ Nationwide delivery (all 50 states)
• ✔ Ships 1-2 business days
• ✔ 30-day returns
• ✔ Secure checkout

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Last updated: April 2026