Magpul M3 PMAG Compatibility Issues

Some Arfcommers have reported compatibility issues with the new Magpul PMAG Gen M3 magazine. The over travel stop on the M3 can prevent it being inserted into some AR-15 lowers with oversized trigger guards. POF, Noveske and Spike Tactical billet lowers have been identified as having this problem.

I asked Magpul’s Drake Clark about this issue. He made this statement …

The M3 design was based off years of feedback from endusers. We knew going into the design phase that there are some lowers that are not going to work with the M3 as the magwell spec they are built to is different from the original Colt design, specifically in the area where the over travel stop interfaces with the area just forward of the trigger guard. These lowers represent less than 1% of the total lowers in the marketplace. We already had direct communication with a few manufactures who build lowers with conflicting interfaces, including POF. Changes will be made to their design to allow comparability. When these changes will be introduced into full production I am not sure. I can say some that have recognized this issue have already been addressed it, such as Noveske.

And for those that have older design lowers that are not comparable with the M3, they have two choices. Use the MOE PMAG or modify the M3 by removing the over travel stop to allow for proper interface.

In all fairness to Magpul, the M3 is compatible with more firearms than any of their previous PMAGs. For >99% of users this will not be a problem. I expect the few manufacturers who are producing incompatible designs will soon change them, it being an easy issue to address.

[ Many thanks to jdun1911 for the tip. ]

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.


  • Zack991

    Another reason I will stick to my old and reliable metal GI mags.

  • A. Hodges

    Meh, shite happens. People just need to learn that everything isn’t about them and that occasionally they will be left out. It happens to everyone eventually.

    • SiloZen

      That’s just karma waiting to happen.

  • Ben Dexter

    Yeah, that sucks, but it’s probably the best solution from earlier Magpul polymer mags where the mag catch being would get worn away by the mag release, allowing for the magazine to be over-inserted.

  • gunslinger

    so magpul is at fault for not designing their product to work with other products that aren’t in their design spec? it’s almost like saying if i buy Microsoft Ofiice for windows, it should work for Mac, Linux, Android and Web OS, all with the same cd??

    but good on magpul working with the other companies.

  • Noodles

    It appears the MEGA billet lowers would be ok, but I’m curious to see that confirmed or not. Anyone?

    • Noodles

      Nevermind, I found it confirmed that the M3 mag does fit in MEGA billet lowers.

  • MrMaigo

    That’s nothing 3 seconds with a dremel won’t fix.

  • Alan

    With the diversity of AR-15 lowers on the market, it would have been unreasonable to expect the M3 PMAG to be 100% compatible with all of them.

  • 6677

    At least its polymer, shouldn’t need much in the way of tooling that isnt already out lying around the house to get that stop off. 30 seconds with a hacksaw or dremel, maybe a bit longer with an old fashioned file. Hell, careful cutting with a bread knife would probably get that lump off (I’d be careful, huge knife for such a small little stump).

  • Raven

    And Magpul completely misses the point of STANAG/mil-spec. Look, there’s a reason that AR mags are standardized, and if you make them outside of that specification, be ready for a whole pile of complaints.

    • Flounder

      LOL I’m trying sooooo hard not to flame here!!!! The issue this gen of Pmag is having is with lowers that have a ridiculous triggerguard…

      So to put it simply this “mil spec” Pmag is not working in lowers that are NOT “mil spec”…

      And if you did have a lower you could always do something to that little nub on the mag to… make it go away… ;D and then it would work perfectly.

      • Raven

        What gets me is this: what possible reason do they have to put the little nub on the rear of the mag where it will interfere with weird lowers? Why not have it on the front, where the only thing it /might/ interfere with is those godawful mag well grips?

      • 6677

        I think it may interfere with some bullpup rifles on the front.

        In my opinion they should have just left the nub out completely.

  • W

    well they fit in my TI BDX15 lowers, DD and Larue ARs, and SCAR, so i guess im good to go.

    Ill buy them as soon as my previous gen pmags and USGI mags wear out. They still have many years of wear left in them.

  • Mike Knox

    Should they really need to complicate simple things? G.I. Mags are a lot simple and more abundant..

  • Kevin

    I’ll just keep using my GI mags.

    • Kevin


    • For those wondering what the benifit of the PMag over USGI ALU magazines are, the largest benefit is reliability over multiple field conditions.

      Both the military and others have compiled pretty extensive data regarding the benefits of the PMag over USGI ALU magazines. This data has now been proven in large sample sizes in actual combat operations over the last 5 years.

      Here is what I have posted before in way of an explanation.

      PMag internal geometry uses an aggressive constant curve to improve reliability (the USGI has a curved then straight section to work with the original M16s straight mag well)
      PMag has a floorplate that is easier to remove and more robust than a USGI
      PMag body has better crush strength than a USGI
      PMag feedlips have better impact strength than a USGI
      In combat deployment after-action reports, the PMag far out lasts USGI mags in theater.
      A PMag body will almost always show a visible sign of damage PRIOR to the magazine becoming non functional. USGI magazine damage is not always apparent until there is a failure of the magazine during firing.
      PMag has a corrosive resistant stainless steel spring, USGI uses stock music wire (Stainless steel spring only very recent USGI mags)
      PMag has a 4 way anti tilt follower as standard (only very recent USGI mags have this)
      PMag is functional after a 500 hour simulated salt spray test (the older green follower USGI fails)
      PMag has a dust cover (that is optional) but will keep dust and debris out of the magazine during long term storage.
      PMag has a much, much lower IR signature than a USGI
      PMag body is easier to handle in both extreme hot and cold temperatures.
      PMag has color options and it’s color is embedded. USGI finish can wear off.
      PMag has an option for a round count window that can read rounds remaining obscured by the magazine well.
      All PMags go through the same QC control (internal and external gauge check for EVERY magazine that leaves the factory)
      Not all USGI mags are built for the US GOV and not all a built to remotely similar standards.

      It is also worth noting that PMags are in a constant state of revision based upon feedback we receive and new production methods. While the PMag retains the same basic look it started with, it has been continually updated and it’s performance far out shines the original from 5 years ago.

      The newest generation PMag, the M3, which was released a few weeks ago, is the strongest by far. It has the additional benefits of being fully compatible with the the HK 416, SA80A2 and the FN SCAR. It also has a slim line floorplate, additional gripping texture and a paint pen matrix for individually marking your magazines.

      • Mike Knox

        Keeping an old pmag flyer handy, eh leonard?

  • Lance

    Not surprised but can you just saw down the ridge to make them work? Glad they work now in HK-416 as well as traditional M-4 style ARs.

  • Noodles

    Good video of a guy testing the M3 with 300blk. Seems to be the same or better than the old PMAG.

  • John Doe

    A few second with sandpaper or a Dremel? Or buy older ones? It’s not like this can’t be worked around. It’s not even like the older ones are bad either.

    • Joseph

      Older pmags didn’t fit either. POF apparently once cause it was because Pmags aren’t made to “spec”.

      E-mags probably would work, though.

      • Joseph

        Oops, typo.

        “POF – apparently once said – … “

  • Brandon

    Does a magazine really need an overtravel stop to begin with? Wasn’t aware it was an issue

    • Sian

      It isn’t with AR15’s, but I think particularly with the SA-80 it could be.

  • I for one am very excited to see the M3 since I only run SCAR rifles these days.

  • Joseph

    So the E-mag is a good option for some folks still.

    • Will they keep making the EMAG? I would think they would eventually drop it for a 1-product solution. From a business perspective, I would. Especially if the relative percentage of EMAGS sold is low.

  • Sian

    I got some of the first run of the gen3, and they’re really nice. DD forged lower, so I anticipated no problems of course.

  • ksenter

    for all you folks that think its a requirement to have the newest latest greatest, I will accept your discarded gen2 mags as I’m sure they will still work just fine for many years to come.

  • tet

    Bought 2 and they don’t fit the msar e4. Guess I stick with the gen 2.

  • Mouse

    “POF, Noveske and Spike Tactical billet lowers have been identified as having this problem.”

    Funny, I always thought Magpul had the problem, since they’re the ones that refuse to adapt their product to what is already out there, despite the fact that many people have complained about compatibility issues.

  • Chelsea Richards

    Atleast there are things new to it like the slide has an overtravel stop to guarantee it can’t head off to far into the magwell which can cause problems with the jolts on non-AR rifles and Modified external/internal geometry so they might be utilized as a part of different stages to incorporate the Hk416.

  • vstewart5

    I have 2 different lowers a cmmg and a stag arms and had the same problem with the mag not setting and when i added the fab defense magwell grip they definitely didn’t work at all so i took all the magpul mags to the grinder and removed the nub from the back and now they work fine but i guess my question is will over travel be a issue?