Armatac Quad-Mag

Armatac emailed me a photo of their new prototype Quad-Mag. The Quad-Mag is a 5.56x45mm quad stack magazine with a 60 round capacity.

It differentiates itself from other quadstack magazines by having two separate feed channels. When the first feed channel is empty, it switches to the other channel. Essentially its two 30 round magazines in a small package. This reduces jamming in the part of the magazine where quad stacks are reduced to a duel stack for feeding.

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Does it work?

  • Kenny

    This is actually a great idea if it works right… merging two staggered column feed paths requires pretty precise geometry. In theory I would trust this over the Surefire mag.

    But I wonder why nobody’s made a mag with a coiled bar spring like Stoner designed in the 70s, that could potentially reduce the mag length dramatically. I guess it wouldn’t work well with fullering.

    • Other Steve

      Except with 300blk, I’ve heard OK reviews about the Surefire, just anecdotes, but still.

      • Matt Gregg

        I’ve got a 60 round Surefire mag, I’ve only put 60 rounds threw it so far but no failures with those first 60.

  • Bandito7j62

    lookin’ at you IAR

  • Brandon

    Why does the video say ‘Prototype coming 1/1/09’?
    Why are they using Also Sprach Zarathustra for their music?
    And how much will that thing cost?

  • SpudGun

    I’m really fascinated to know how this works. Does the follower from one feed channel actuate the other feed channel? Is the switch between channels instantaneous or is there a delay between feeds? (Couldn’t tell from the video as it was all burst fire with no continuous mag dump)

    • Rade


      As far as I can tell it should look something like this internally
      now this is just a quick drawing I made but the real mag shouldn’t be that different, as you can see the mag will first feed the rounds from the right side of the mag until the follower in the right side reaches the ramp where the mag converges from the quad stack to the double stack where the right follower would stop, at this point the lever which is holding down the rounds in the left side of the mag would flip to the right and the mag would continue feeding the rest of the rounds from the left side until its empty.

      Also note how there is fewer number of rounds on the left side of the mag, by doing this you have more room on the left side for the longer spring which needs to push the left follower all the way up to the feed lips, unlike the right follower which only needs to get to the point where the mag converges to double stack.

      • SpudGun

        Hi Rade,

        Thank you very much for the drawing and the explanation. It is a very clever design and I hope it proves to be reliable.

        It certainly looks a lot simpler then many of the quad stack designs, so hopefully that will equate to fewer malfunctions.

        Good luck with it, I hope it’s a success.

      • W

        thank you rade, a picture is worth a 1000 words. theoretically, this should make the magazine very reliable and durable. Hopefully somebody can invent a durable and reliable extended magazine that is more manageable than those drums.

      • JMD

        That’s clever and simple. Simple is good.

        Thanks for the sketch.

  • W

    it would be nice for a very reliable and practical extended magazine to be developed so that the IAR can become more effective.

  • Lance

    This is a competitor to the Surefire 60rd mag for a possible USMC contract for a special mag for the IAR M-27. If this is cheaper than a surefire than im in looks cool and has good steel in it to keep the mag durable something the Pmag lacks. I like the surefire looks but it too expensive, so I hope this will be cheaper.

    Forget Gunny approved this mag is K9 approved! 😉

    • W

      the Pmag doesn’t need steel in it because they are plenty durable. I believe this Armatac magazine should be tougher than the Surefire one, simply because it is constructed of polymer with a alloy to reinforce critical parts. Itll be nice to see something better for the IAR, so our military lads don’t have to flounder with those mediocre GI Spec magazines.

      Color me shocked, but it is unbelievable, if criminal, that the Soviet military developed reliable drum and extended magazines for their RPKs, but we still are trying to come up with one that is at least applicable (in the 21st f–king century, we are using 30 round magazines with our IARs that we also recently fielded).

  • schizuki

    Finally, a product to help me melt my barrel.

    • 9mmLargo

      Nah, you’ll get cook-offs long before that 🙂

  • Komrad

    Quad stack vz. 58 mags, quad stack vz. 58 mags, quad stack vz. 58 mags.

    Nope, didn’t work. Guess I’ll have to stick with 30 rounders.

    This design looks more reliable than just merging the columns and it should be expandable to more than just quad stack, at leas based on Rade’s drawing. It shouldn’t be that hard to put another stack on the one side that just feeds into the middle stack. I like that more because it is a general solution for adding columns, rather than a finicky merging system. (note, I am not suggesting that a hex stack or octo stack mag would be at all practical or desirable)

    My only concern is the same as Spudgun’s, that is, delay in switching between columns. It shouldn’t matter if there is a delay so long as it is shorter than the time between rounds for a given weapon’s ROF.
    I’m also interested in the way it is loaded. Does the toggle switch back automatically? Is it possible to load differing amounts into the columns? Is it possible to only load one column? How long until someone “pins” this to 10 rounds for sale in California?

    The Finns tried quad stack mags back in the Winter War for the Suomi M31 SMG and they didn’t work too well 9although they did work). It’s interesting to see that they are only just now making a resurgence with a lot of innovative stuff coming out. Can’t wait to see the final results when quad stack becomes commonplace. It may replace drum mags altogether.

  • Big Daddy

    The question is, how reliable is it? Is it reliable enough for a tactical situation were your life is on the line. Or is it a toy to have some fun with like burning out the gas tube on your AR.

    Was it me or was the magazine rocking back and forth in the video? How does that affect the weapon? The inertia could affect the weapons function, is that possible? Was it loose fitting, is that why it was moving?

    • Charles222

      M4 magazines, in my experience, are always kinda loose-fitting; pretty sure it’s to do with the fact that they’re attached only to the magazine release.

  • W

    Oh and on a final note, i wonder how this magazine can compete with the Russians’ AK74 quad stack magazine? I recall a post on this blog about such a magazine and i cant find it for the life of me. If i remember correctly, the Russian magazine utilized a “diamond” like angle in the middle, which effectively resulted in a seamless merge of the two columns of ammunition.

  • Surefire

    Why does the official video have “SUREFIRE 60” (by the poster) in the description…..