High-Cap AR Mags

From left to right: DPMS, CMMG, Brownells and Lancer magazines…

From left to right: DPMS, CMMG, Brownells and Lancer magazines for greater capacity in a firefight. Guy Neil photos

Extended Magazines
Virgil Tripp developed the STI 2011 pistol frame using a stagger-stack magazine in a 1911-pattern gun. Tripp now offers improved 1911 magazines and, more recently, extended AR magazines in two configurations. He builds 42- and 52-round magazines by adding extensions to the standard 30-round box.

The Tripp magazines are popular with practical rifle competitors—demanding shooters who will not tolerate poor performance. The extensions are robust and able to withstand being dropped on the ground, though there is little need to drop them on the ground since reloading is eliminated or minimized.

The extension offered by Nordic Components also shows the popularity of Magpul PMAGs. Their extension expands the PMAG capacity to 48 rounds.

Thermold has a 30-round magazine that extends to hold 45 rounds. This dual nature allows the tension on the spring to beeased when there are only 30 rounds loaded, but still allows the full 45-round capacity.

CMMG offers a 42-round magazine made of steel instead of polymer or aluminum. It is built from the start as higher-capacity magazine—not adding an extension. They are just like the standard military magazines, but longer. Lancer also has a polymer 48-round magazine billed for competition.

The DPMS higher-capacity magazine takes a standard 30-round tube but has an extension welded onto it that allows for 47 rounds.

The current Brownells 30-round AR magazine was used for a baseline comparison. Brownells is a military contractor, so there’s none better for comparison. The Brownells magazines are first class and recommended if you need 20- or 30-round magazines for your AR.

Lancer’s polymer, 48-round extended magazines are designed specifically for competition.

More With 30
You may stay with the 30-round magazines but add ammunition capacity by coupling two magazines together. There are numerous available, but I tested the Brownells coupler with their magazines. The coupler mounts two 30-round magazines side by side for a fast reload that requires little motion, other than withdrawing the empty magazine and inserting the full one.

Prezine, headed by Bill Rogers, a holster design wizard, offers a coupled magazine using the Magpul PMAGs. This is a fixed unit that comes assembled. PMAGs are popular because of their reliable performance, so coupling two of them is a logical step.

There is a wide variety of higher capacity magazines available for your AR. If you have need of more ammunition, the solution is available to fit your needs.


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Load Comments
  • Scarlighter

    There are also Armatac, MWG and XS-Products with their High-Capacity Magazines, and the largest for a 5.56 AR is the Armatac SAW MAG (150 Rounds).

  • J Hughes

    CMMG does not list any such 45rd magazine on their website. Please correct your article.

  • J Hughes


  • J Hughes

    And DPMS offers a 45rd magazine, not a 47rd magazine.

  • Bill Johnson

    You state that “The highest-capacity magazine currently available is the Beta Company’s C-Mag.” I would urge you to research a little better and you will find out that ARMATAC (http://www.armatac.com/) has been in business for quite some time and have been making quite possibly the best Hi-Cap mag of 100 or more rds. for years now! Their CL-Mag is a 150 round rotary mag that requires NO LUBE EVER!! Please check them out! I wish thagt their discontinued models made of all billet aluminum were still being made!!

  • J Hughes

    I just ordered that Nordic Components Pmag extention kit and a 30rd Pmag. Probably gonna krylon the whole thing OD green. Too cheap to duracoat a magazine.

  • Guy Neill

    Thanks for the comments.

    Several of the manufacturers did not respond to my inquiries while others, I admit, did not come up in my efforts to seek out those available.

    I’ll continue to try to contact the various manufacture’s and, hopefully, be able to provide a follow-on article with those not already covered.