The Mossberg 590A1 Optic-Ready Threaded 12 gauge is the most durably built pump in the company’s lineup, with a service record across military and law enforcement agencies (Mossberg part no. 50799). A heavy-walled 18.5-inch barrel takes the Accu-Choke system with a cylinder bore choke installed, and the Parkerized finish covers the metal. The receiver carries an optic cut for Shield RMSc-footprint sights, and the M-Lok compatible forend adds accessory slots. Metal trigger guard and safety, a clean-out magazine tube and a drilled and tapped receiver are standard. This Mossberg is a popular choice for home defense.

Key Specifications

• Gauge is 12 gauge with a 3-inch chamber, handling a wide range of shell types.
• The barrel is 18.5 inches and heavy-walled, a tough profile for duty-style use.
• The barrel is threaded for the Accu-Choke system, with a cylinder bore choke installed.
• The finish is Parkerized, a durable, low-glare coating on the metal.
• Capacity is 6+1, a practical reserve for home defense.
• The receiver is optic-ready for the Shield RMSc footprint, so a micro red dot can mount directly.
• The forend is M-Lok compatible with accessory mounting slots for lights and grips.
• The stock is black synthetic with a spacer, with an adjustable 12 to 13-inch length of pull.
• The trigger guard and safety are metal, a more durable alternative to plastic.
• Sights are a bead front, simple and fast on a close-range shotgun.

Frequently Asked Questions

Is the 590A1 optic-ready? Yes. It has an optic cut for the Shield RMSc footprint, so compatible micro red dots can mount directly.

What choke comes installed? The barrel uses the Accu-Choke system with a cylinder bore choke installed.

Can I add accessories to the forend? The forend is M-Lok compatible with accessory mounting slots.

Buy the Mossberg 590A1 Optic-Ready Threaded 12 Gauge Pump Shotgun

The 590A1 is the version most buyers picture when they think of a hard-use Mossberg, and the optic cut and M-Lok forend bring it up to date. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL, and see more pump-action shotguns too.