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It’s becoming pretty clear that the now-ubiquitous quadrail forends on firearms are just too bulky to be useful. They make attaching things a breeze, but the cheese grater effect and the tube diameter required to make it work is just way too clunky. It’s the reason that we’ve seen the increasing move toward the keymod as the new attachment system to end all attachment systems, an “open source” standard developed originally by Noveske with help from VLTOR. But now Magpul appears to be trying to introduce their own standard, dubbed the “M-LOK” system, that uses straight slats instead of keyed holes . . .


From their announcement:

M-LOK is a modular locking accessory mounting system that is a direct attachment method for hard mounting accessories to a negative space mounting point. Designed by Magpul Industries as an evolution of the MOE slot system used since 2007, the M-LOK system is being released as a free licensed platform to allow greater compatibility of accessories between all manufacturers.

From my armchair, it looks like a “too little, too late” effort to start a new standard. Keymod has been widely accepted by the best in the business, and just like Betamax before it, this new standard might just fade into the distance. But there’s one very good thing about this announcement: Magpul is releasing the M-LOK system royalty-free. So anyone can use it without having to pay Magpul for the privilege.

Magpul is probably the most popular rifle furniture manufacturer in the world, and if they push the new standard hard enough then there is a good chance that they can force people to adopt their standard as the “one slot to rule them all.” But with the huge headstart that keymod has, it will be an uphill battle. I’m just happy that people are recognizing the need for a new flat mounting system to replace (or supplement) the existing Picatinny standard.

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  1. Haven’t they been doing this for years on their AR handguards? I have quite a few rail sections and Magpul only for grips for it already.

  2. Honestly, its all about the weight for me(Maybe I just have a heavy rail, been looking at the Geissele and DD ones lately), always had some rail covers or gloves. I may just be going back to the MOE forearm etc for that reason.

    I like how theyre trying to design a more universal attachment system for all the various flavors of rail out there.

    EDIT: 🙂 @ the Betamax comment. Do you remember how super cool MiniDiscs were in the 90s?

    • they were cool enough that I only knew maybe one person who had a portable MD player/recorder and a sizable library of all the late 90s hits, and he was showing it off all the time at school.. five years later it was totally obsolete and a worthless investment.

    • He was using it wrong then, buying prerecorded discs was stupid. Minidisc was useful as a portable digital audio recorder back before sd cards and solid state memory got cheap, especially once the Hi-MD (1gb) recorders came out. Those could record over 30 hours onto 1 disc at 64kbps. They didn’t even need the stupid atrac format anymore, they played mp3’s. You could upload and download the tracks by usb into your computer to edit them then save them back. The recorder players from Japan were also tiny as heck, just 2x as thick and nearly the same size as the discs themselves. I miss mine, it got stolen at a school district tennis match (I took the alternate spot so I could miss school, had been playing for a week to qualify.)

  3. The Picatinny rail standard isn’t 100 years old. The itself standard is 20 years old. Or 30 years old if you want to push it back to the mid-80s when ARMS developed it.

    • You’re right. It was developed in the Late 80’s through the 90’s and adopted by the DoD with the Mil Spec MIL-STD-1913 in 1995. But many people confuse the spec number with the date it was adopted.

      • I took the “100 year old” statement to imply that your weapon is considered old fashioned if it has the old fuddy-duddy 4 sided cheese grater.

        • I was unaware fudds liked anything other than wood. Kind of an unrelated reference 🙂

          Although since you can buy quite a few MSRs at Wally World now, I bet there are a few upgraded ones runnin around.

    • I think he’s basing that number off of the military designation, M1913 Picatinny. Since the M1911 was adopted in 1911, it could be confusing to those who mistrust Google and it’s many answers.

  4. HD-DVD had a larger market share as well as the “blessing” of the P0rn industry, and they still lost. The argument can be made that the PS3 owners were who won the last format war for Blu-Ray, Magpul “fanboys” could well do the same here. A large, well funded push of a royalty free standard by one of the biggest names in accessories is exactly what could kill off keymod.

      • You mistake my quoted use of fanboys as inclusive of all Magpul users. It is directed at only a specific subset of users, much in the same way there are millions of people that use an iPhone that would not be considered Apple fanboys.

      • I prefer to buy my content not rent until the content streamer service dies, or stops running authentication servers, or doesn’t pay the license to be able to stream the content…

    • PS3 plus the treachery of Warner Bros.

      (don’t get me started…)

      ObTopic: I wonder if they’ll have M-LOK forends for the ACR? I find the MOE foregrip a bit wobbly on mine, but I could be doing it wrong. (I wonder when the 300BLK barrel swap is coming too, but I’m not holding my breath :p)

      • Only way anything meaningful is gonna come out for the ACR is if somehow Magpul buys it back from Freedom Group.

        • “full.tang.halo says:
          Only way anything meaningful is gonna come out for the ACR is if somehow Magpul buys it back from Freedom Group.”

          Amen to that. The Masada had promise.

  5. I think I like this more than keymod. Keymod is nice, but wouldnt it require accessory manufactures to re-tool/change the manufacturing process up in order to do direct attachment of accessories like VFG and flashlights(thats all I really use on my weapons’ handguards)?

    • If you read the PDF announcement it states that this new system is both stronger and cheaper to make than KeyMod. Also the slots remove more material (some call this negative space) than Keymod which should lead to weight savings.

      I need to bust out the pop corn and sit back and watch the KeyMod/M-LOK battle.

  6. So lots of things to say here.

    Quad rails work just fine. I have Centurion Arms rails on a few guns, and they are both light weight and they are machined so well that I don’t run any covers on them. I don’t need a glove either if I don’t want one. Yes I have used some fatter and much sharper ended (Troy) quad rails and they are not on my rifle for those reasons. My Mid-Lenght cut out rail is 12 ounces with barrel nut and screws. Yes that is more than say the BCM KMR at 7.7 ounces, but I don’t have to add rail sections or a QD mount since I already have them. My Centurion rails barely, I mean barely, get warm after 3 mag dumps (barrel and A2 front site is hot as hell). The Centurion rails also use the standard barrell nut which to me is a plus vs proprietary nuts that some of these rails use.

    The military (US and others) uses quad/picatinny rails so any new invention (Key Mod or M-LOK) is not going to get the same traction until the military adapts it.

    Yes KeyMod is all the rage right now, especially for youtube gun shows, and I think the BCM KMR is a great but I have also read some negative things about Keymod, like stuff falling off of them under stress. Also Keymod accessories are not really showing up that fast. I am not a ver grip guy but even BCM does not have their grip out yet for KeyMod.

    Magpul is great at marketing. They are great at low cost accessories. If you read the PDF they are moving everything they make over to this new standard and even Geissele has a M-LOK rail already. Also Magpul makes some claims about strength in that PDF that if true is going to make a good case against Keymod. How many MOE handgaurd owners could move to a new M-LOK hand quard that is probably slimmer and lighter for under $50? That PDF sates they will be launching all new versions of MOE products with M-LOK in 2014.

    KeyMod is far from the defacto standard for new rails. Quad rails live on and will for a long time. Magpul has a ton of marketing and manufacturing power behind what they do. Magpul almost never releases a dud of a product.

    • Any bets on largest market today for AR15/M4/M16? US mil or civilian. Given Obuma shutting down the mil I’d bet, by large margin, is US civ market.

  7. yeah, little late to the game here. and Magpul doesn’t make freefloat forearms last I remember, so not sure they should be calling the shots on a new standard. Shouldn’t it be better be dictated by the actual forearm manufacturers and not the accessory manufacturers?

    If they really want to knock something out of the park, they should expedite their Gen2 AK Moe Magazine (with steel lockup points) – and maybe even incorporate a yugo-style bolt hold open feature?

    just my .02c

  8. My personal favorite is 8-10″ of rail, but variety is a good thing. Two of my ARs don’t even have rail (the horror!). I like the quality and politics of Magpul, so I may just check this out.

    • I’ve got a 9″ Troy alpha rail on my pistol. Nice, round, and free float with no cheese grater. Apparently rails can attach but I don’t really care.

  9. Huh, imagine that. I thought I was the only person who hates the way that quad rails feel in a hand with no glove. I just might have to check this out at some point.

  10. OK, so now we have an additional mount to deal with AND an additional key to work the whole set up?

    Newer is goodder, indeed….

  11. Huh. Was reading weight comment above and reailzed this uses much more “blank” space, so could actually be a little lighter than keymod systems.

    Interesting development either way.

  12. Hmm. Keymod and M-LOK seem great and all, but I’m pretty happy with my YHM quad rails. Call me old-fashioned…I guess.

  13. Yo dawg, I heard you liked universal attachments, so I put a universal attachment on your universal attachment so you can operate while you operate.

  14. Im biased, because I just dropped some coin on a BCM KMR13, but the keymod looks a lot more secure. The screws would have to be loosened well beyond the point of the accessories rattling around the for locking lug to unhook and lose the accessory. Unless there is some sort of backup these new magpul rail sections would just have to work loose enough for the locking lugs to rotate 90 degrees and then the section would fall off with what seems to me, a fair bit less warning.

    The keymod accessories I have now would be rattling and moving around noticeably long before they were able to just slip off the rail, kind of like a round manhole cover, it would be very hard for the round beveled lug to just pop directly out. It has to be loosened sufficiently to where the locking lug can disengage and slide to the rear. I don’t see this making it very far. Just wait till some operator over on ARFCOM loses there $300 tactical light mid operation and the Magpul rail will get the blackball.

    • Justify that Keymod purchase 🙂

      Both look secure. From Magpul’s press announcement they state….

      M-LOK has lower manufacturing costs (so costs less to the consumer)
      M-LOK has better pull out strength.
      M-LOK has better recoil/impact mitigation.
      M-LOK accessories are front and rear directional.
      M-LOK can use the millions of MOE accessories already produced.

      If the NRA showing of M-LOK goes well this weekend…..KeyMod market penetration will drastically slow.

  15. Keymods and this new M-LOK are definitely sexy. I wanted to replace my DD M4 12″ quad rail with one but I already paid an arm and a leg for it. Not that price stops me (if anything it slows me down) I just want an awesome rifle. But a huge concern to me is weight, I figured I would save some by switching to a keymod. Uh uh. After looking up weights of some of the best guys out there: Noveske, PWS, Geissele, etc. I found no appreciable weight savings. Many were still within shaving an ounce if anything at all. Start adding rails on it and I’m sure the weight goes up enough to make the swap downright pointless.

    The rails don’t bug me at all either. The DD M4 is already the skinniest quad rail of the lot and close to being the lightest. Slap on some ladders and it isn’t bothersome in the least. Probably not as comfy as a keymod but not worth the swap.

    Just my two cents.

    • IMHO Quality rails do not need any covers.

      On my Centurion Arms rail the only rail pieces covered are a section of the bottom rail where my Magpul XTM hand stop kit is, and on the 9 o’clock rail I have a thorn tail light mount. The rest is bare and my hands love it that way.


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