Mossberg 590RM Mag Feed Stand-Off Shotgun 12ga 10rd Magazine 18.5" Barrel AR-Style Rotary Safety

The Mossberg 590RM Mag Feed Stand-Off Shotgun brings modern, modular design to pump-action shotgun performance. Built on Mossberg's reputation for rugged reliability, the 590RM ditches traditional tube magazines for a double-stack, magazine-fed system that delivers more rounds per unit length—a genuine advantage for tactical and home-defense shooters who demand capacity without sacrificing maneuverability. With its 18.5" barrel, integrated heat shield, and AR-platform ergonomics, this 12-gauge stands ready for serious work.

What sets the 590RM apart is its thoughtful operator-focused design. The AR-style rotary safety selector is ambidextrous, the compact forend reduces hand fatigue during extended shooting, and the 5-position adjustable stock with MOE+ pistol grip lets you dial in your fit. The top Picatinny rail is optimized for AR optics, so your favorite red dot or low-power variable scope mounts naturally. A flat-profile trigger with a crisp, predictable break rounds out the controls. Standard pump-action guts—dual extractors, steel-to-steel lockup, and twin action bars—deliver the reliability you expect from Mossberg's proven platform.

The 590RM ships with Mossberg's proprietary stabilizing-rib magazines; the base model includes one 10-round magazine (10+1 in the chamber). Aftermarket magazines are available in 5, 10, 15, and 20-round capacities, so you can configure loadouts for different missions. Accu-Choke compatibility lets you swap chokes to match your ammunition and intent. Whether you're running a defensive setup, running a course, or setting up for hunting, the 590RM adapts without compromise.

This is a shotgun built for shooters who think tactically but demand proven function—no gimmicks, just smart engineering and battle-tested durability.

Key Features

• Magazine-fed 12-gauge pump action with double-stack magazine design for efficient capacity
• AR-style ambidextrous rotary safety selector for familiar operation
• 18.5" barrel with integrated heat shield for stand-off distance and reduced muzzle signature
• 5-position adjustable stock with interchangeable recoil pad and MOE+ pistol grip for modular fit
• Top Picatinny rail optimized for AR-platform optics
• Compact, ergonomic forend designed for extended shooting
• Flat-profile trigger with smooth, crisp break
• Dual extractors and twin action bars for reliable operation
• Accu-Choke compatible barrel
• QD mounting ports (2-sided) on stock base
• Includes one 10-round magazine; additional 5, 10, 15, and 20-round magazines available

Specifications

Frequently Asked Questions

What makes the 590RM magazine system different from traditional tube-fed shotguns?

The 590RM uses Mossberg's first double-stack magazine design for pump-actions. This delivers more ammunition capacity in a shorter overall length compared to traditional tube magazines, making it ideal for shooters prioritizing both ammo count and a maneuverable profile. Magazines are available in 5, 10, 15, and 20-round options.

Can I use AR-platform stocks and accessories on the 590RM?

Yes. The 590RM stock base is compatible with Mil-Spec AR-style stocks, and it features the adjustable MOE+ pistol grip. The top Picatinny rail is optimized for AR optics, and the QD mounting ports support quick-detach sling systems. The rotary safety selector is AR-style and ambidextrous, so AR shooters will feel at home immediately.

What ammunition does the 590RM accept?

The 590RM chambers 2.75" 12-gauge shells and ships with one 10-round magazine. It is Accu-Choke compatible, allowing you to swap chokes to match your ammunition type and application (Cyl. Bore or Breacher options are noted).

Is this shotgun suitable for home defense or tactical training?

Yes. The 18.5" barrel, magazine-fed capacity, AR-platform ergonomics, and modular stock system make the 590RM well-suited for both roles. The integrated heat shield provides stand-off distance and helps manage recoil signature, and the Picatinny rail accommodates optics for faster target acquisition. Mossberg's proven pump-action reliability underpins it all.