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IA Iron River Armory

Mossberg 590RM Mag-Fed 12 Gauge 18.5″ Pump

SKULIP|MB50218 Conditionnew CategoryPump Action Shotguns
$853.35
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About this product

The Mossberg 590RM is a 12 gauge pump-action platform configured for magazine feeding and short-barrel stand-off use. It features an 18.5-inch stand-off barrel with an integrated heat shield, a 5-position adjustable stock paired with a Magpul MOE pistol grip, and a top Picatinny rail for optics and accessories. Built on an aircraft-grade aluminum receiver with a parkerized finish, the 590RM is designed for security and tactical applications where compact handling and modularity matter.

Key Specifications

  • The gauge is 12 Gauge.
  • The action is Pump-Action.
  • The barrel measures 18.5 inches and uses a stand-off design with an integrated heat shield.
  • The chamber accepts 2.75″ shells.
  • The stock is a 5-position adjustable unit with a Magpul MOE pistol grip and interchangeable pad.
  • Sights and mounting are provided via a top Picatinny rail.
  • The receiver is aircraft-grade aluminum.
  • The finish is parkerized.
  • Length of pull is 12″–15.25″ (adjustable).
  • The barrel uses an Accu-Choke system with a cylinder-bore choke indicated as included.

The 590RM blends Mossberg’s proven pump-action reliability with a magazine-fed configuration and compact stand-off barrel to deliver a versatile, modular platform for security-minded users. Its adjustable ergonomics, corrosion-resistant finish, and options for optics and accessory mounting make it a sensible choice for those who prioritize durable, adaptable equipment with straightforward serviceability.

Specs at a glance

Mossberg 590RM Mag-Fed 12 G… SPECS AT A GLANCE 18.5 inches SIZE
Editorial diagram — measurements verified during testing.
Sources & methodology. Editorial review and rating by Travis Caldwell based on hands-on testing notes and published vendor specifications. Pricing verified at time of publication.
$853.35