MAG MSBRG 590M 12GA 10RD DBL STK BLK

Description

The Mossberg 590M magazine is designed for shooters who run the 590M mag-fed shotgun platform and want a reliable, factory-spec source of additional capacity. Because it comes directly from Mossberg, the feed geometry and tolerances match the original equipment exactly — there is no fitting or modification required.

The double-stack arrangement is worth understanding. A single-stack 12-gauge magazine grows long quickly because each shell sits one behind the other in a straight column. By staggering the shells in two columns, the 590M magazine holds ten rounds while keeping overall length shorter than a single-stack design of comparable capacity. That shorter length affects how the gun handles: less magazine protruding below the receiver means less leverage working against your swing and transitions between targets.

Construction reflects the demands of the shotgun environment. The magazine body is built from a self-lubricating polymer, which reduces friction during feeding without requiring the shooter to apply anything to the interior. Steel feed lips are hardened and finished in black oxide to resist deformation under repeated loading — feed lips are the component most likely to fail on a high-cycle magazine, and using hardened steel rather than polymer for that specific part is a deliberate engineering choice. Shell ramps are steel as well, over-molded into the body, to guide each 2¾-inch hull consistently into the chamber. The spring is ASTM A-228 music wire, a high-carbon steel specification chosen for its resistance to fatigue over long compression cycles. The floor plate is removable for cleaning and inspection. This magazine accepts 2¾-inch shells only.