Mossberg 590M, the world's first double-stack mag-fed shotgun

Mossberg 590M, the world's first double-stack mag-fed shotgun
Blade City

The Mossberg 590M shotgun features a double-stack magazine ranging in capacity from 5 to 20 rounds. Double-stack shotgun magazines were first reported as “in development” back in 2012 when MD Arms’ Michael Davidson filed a patent for the innovative shotgun accessory.Blade City

Built on a classic scattergun, the new 590M is perfect for home defense, tactical training, and competition purposes. The pump-action shotgun is available in 12 gauge 2 3/4″ and comes standard with a pair of 10-round double-stack magazines.

The 5, 15, and 20 round magazines can be purchased seperately. For reference, the 5-round magazine is just 5.375″ tall while the 20-round mags are 12.65″ tall. Each mag is designed for 2 3/4″ shells only and feature a self-lubricating plastic body with steel feed lips and stabilizing ribs. The 5-round magazine weighs just under 1 lb.

Mossberg described their new weapon in their company blog,

Innovation is at the core of the 590M with the detachable magazine’s uniquely-designed, integral stabilizing ribs which engage the magazine directly to notches engineered into the receiver, ensuring a positive lock-up. The all-steel, heated-treated magazine release button and housing are optimally-positioned in front of the trigger guard for quick, ambidextrous access for unloading and reloading the 590M. The location of the mag release does not interfere with cycling of the action. The well-executed design allows for proper balance, better swing and controlled-manipulation with a full-magazine located at the center of gravity point.


  • Gauge: 12
  • Capacity: 5, 10, 15, or 20 +1
  • Barrel: 18.5″ Heavy-Walled
  • Weight: 7.75 lbs
  • Overall Length: 39.5″
  • Sight: Bead
  • MSRP: $721 – $801

Take a closer look at the new Mossberg 590M on the range in the video below.