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Product Discontinued by Manufacturer

USED, Magpul Industries PMAG GEN M3 AR-15 Rifle Magazine, .300 Blackout, 20 Round, Black, 1 Pack, Polymer, MAG1182-BLK-20RD has been discontinued by Magpul Industries and is no longer available. Our product experts have helped us select these available replacements below.You can also explore other items in the Magazines, Rifle Magazines, AR Rifle Magazines yourself to try and find the perfect replacement for you!

Product Info for USED, Magpul Industries PMAG GEN M3 AR-15 Rifle Magazine, .300 Blackout, 20 Round, Black, 1 Pack, Polymer, MAG1182-BLK-20RD

The USED, Magpul Industries PMAG GEN M3 AR-15 Rifle Magazine, .300 Blackout, 20 Round, Black, 1 Pack, Polymer, MAG1182-BLK-20RD Color: Black, Magazine Body Material: Polymer, Fabric/Material: Polymer, Magazine Capacity: 20 Round, Caliber: .300 AAC Blackout, Gun Make: AR Platform, Gun Model: AR-15, Gun Type: Rifle, Quantity: 1 Pack, Condition: Used, Condition Quality: Good, Reason: Other. is here at OpticsPlanet with great discounts Up to $15.95 Off! Please also check out more options for Magpul Industries PMAG GEN M3 AR-15 .300 Blackout 20 Round Rifle Magazine.

Purchase your new USED, Magpul Industries PMAG GEN M3 AR-15 Rifle Magazine, .300 Blackout, 20 Round, Black, 1 Pack, Polymer, MAG1182-BLK-20RD from OpticsPlanet today and you will appreciate the easy checkout process, fantastic customer service, Free Shipping policy and information on easily tracking your order.

The PMAG 20 AR 300 B GEN M3 is a purpose-built magazine for rifles chambered in .300 Blackout (300 BLK). Similar in every way to our PMAG 30 AR 300 B, the PMAG 20 is more compact for increased maneuverability and creates a more concealable package for use in small format firearms.

Since its inception, 300 BLK shooters have had to use a magazine designed for another cartridge, limiting that rounds ultimate performance and compatibility. One of the key features of 300 BLK in the past has been its compatibility with 5.56x45mm magazines. However, even with moderate success with that particular magazine, it is a compromise to do so, with reliability and safety both being at risk.

In addition to the performance gained by a dedicated mag, the PMAG 20 AR 300 B also offers a safer way to feed your 300 BLK rifle. When using 5.56x45mm mags, the potential to chamber and fire a 300 BLK round in a 5.56x45mm rifle with catastrophic results requires diligent ammunition management by the shooter. The PMAG 20 AR 300 Bs distinct ribbed design and smoother upper-half texture provides the shooter a distinct visual and tactile difference from any other PMAG to mitigate dangerous cross-loading issues.

Along with optimized 300 BLK performance, the PMAG 20 incorporates all of our GEN M3 features, including our next-generation impact and crush resistant polymer, aggressive front and rear texture, an easily removable slim floor plate, and a paint pen dot matrix for marking and identification.

Features:

Dedicated, reliable magazine for rifles chambered in 300 BLK that supports the differing geometries found in that caliber

20-round body is more compact for increased maneuverability, creating a more concealable package for use in small format firearms

Distinct rib design and texture provide visual and tactile differentiation from other PMAGs to mitigate dangerous cross-loading issues

Next-generation impact and crush-resistant polymer, aggressive front and rear texture, easily removable slim floor plate, and a paint pen dot matrix

Features of Magpul Industries PMAG 20 Gen M3, .300 AAC Blackout, 20 Round Rifle Magazine

  • Dedicated, reliable magazine for rifles chambered in 300 BLK that supports the differing geometries found in that caliber
  • 20-round body is more compact for increased maneuverability, creating a more concealable package for use in small format firearms
  • Distinct rib design and texture provide visual and tactile differentiation from other PMAGs to mitigate dangerous cross-loading issues
  • Next-generation impact and crush-resistant polymer, aggressive front and rear texture, easily removable slim floor plate, and a paint pen dot matrix

Package Contents:

  • Magpul Industries PMAG GEN M3 AR-15 .300 Blackout 20 Round Rifle Magazine
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Last updated 2026-07-25 UTC.