Mossberg 590M 15-Round Detachable Magazine 12GA 2.75″

Description

Built for the Mossberg 590M platform, this 15-round magazine gives you the extra capacity of a standard detachable mag system without the bulk or length of a single-stack design. The patented double-stack layout keeps the magazine profile compact and centered against your body, which means better balance during firing and easier handling compared to longer tube-fed alternatives.

What Makes the 590M Magazine Different

The real advantage here is what the double-stack design does for your shooting. This magazine reduces overall length while packing 15 rounds, so when it's loaded, the weight stays centered near the receiver instead of pulling the front end down like extended tube magazines do. Real-world testing shows that even with the 15-rounder, the 590M maintains excellent swing speed and point ability. You also get instant magazine changes—pull the ambidextrous release button and swap to a different load type in seconds. Want to go from target loads to buckshot? Just swap magazines.

590M Magazine Build Quality

The polymer body uses a proprietary self-lubricating material that resists fouling and doesn't require constant cleaning like some metal magazines. The hardened steel feed lips are paired with over-molded shell ramps to guide rounds smoothly into the chamber, and an anti-cant rounded follower keeps everything feeding reliably. A heavy-duty music-wire spring rated for extended service life handles the spring-back action without degrading. For maintenance, the removable floor plate comes apart easily so you can inspect or clean the internals if needed. Steel components carry a tough black oxide finish that handles salt, mud, and heavy use.

Practical Notes on Loading

This magazine carries genuine capacity. A loaded 15-rounder will weigh around 2.5 to 3 pounds depending on shot type, so it does add noticeable weight to the gun, but that weight is positioned low and forward in the magazine well rather than on the barrel like tube extensions. Loading does require firm, steady pressure—bracing the mag against your body, a work table, or vehicle while you drive rounds down works best. Once you load a few, your hands and technique improve. This is strictly for 2.75-inch shells; the 590M will not accept 3-inch magnum loads.