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IA Iron River Armory

Mossberg 590A1 M-LOK Mariner 12 Ga 18.5in Pump Shotgun

SKURSR|MS50767 Conditionnew CategoryPump Action Shotguns
$803.98
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Specs at a glance

Mossberg 590A1 M-LOK Marine… SPECS AT A GLANCE 18.5 inches SIZE
Editorial diagram — measurements verified during testing.

About this product

The Mossberg 590A1 M-LOK Mariner is a 12 Gauge pump-action shotgun built for reliable duty use in maritime and defensive environments. It features an 18.5-inch heavy barrel with a 3-inch chamber and bead sights for straightforward aiming. The firearm includes an M-LOK forend and a black synthetic stock finished in Marinecote for enhanced corrosion resistance. The design emphasizes robust operation and easy maintenance in corrosive conditions.

Key Specifications

  • Model designation is 590A1.
  • Chambered in 12 Gauge.
  • Barrel length is 18.5 inches for compact handling.
  • Barrel type is a heavy barrel profile for durability.
  • Chamber size supports 3-inch shells.
  • Action is pump action.
  • Finish is Marinecote for enhanced corrosion resistance.
  • Stock is black synthetic.
  • Forend features M-LOK attachment slots.
  • Sights are a simple bead configuration.

The 590A1 M-LOK Mariner pairs corrosion-resistant finishes, a rugged heavy barrel and a modular M-LOK forend to serve in maritime, security and defensive roles where dependable performance matters. Its straightforward pump-action operation and synthetic furniture make it easy to maintain and operate under demanding conditions. For shooters who prioritize durability, simplicity and functional features, this model provides a practical, mission-focused platform.

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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.
$803.98