Gear, Parts and Accessories

Fad or the Future? The KeyMod Rail System

Picture shows a close up of a KeyMod rail system on an AR-15 rifle.

A new rail system for your rifle is slowly catching on. Officially announced to the public in July 2012, the KeyMod mounting system uses old principles to lock down rails and accessories. In collaboration between then General Manager of VLTOR Weapons Systems, Eric Kincel and Noveske Rifleworks, Noveske developed the KeyMod handguard. Noveske’s NSR handguard was first to adopt the new system. The lightweight and thin handguard uses a series of keyholes to mount accessories and rails. Kincel mentioned it was not originally intended to replace the 1913 rail, but some speculate it will.

It works the same way as a lot of shelving and scaffolding. One end of the “keyhole” is bigger, while the other end is smaller. You put your accessory or rail into the larger part of the keyhole and slide it down to the smaller end. With a few quick turns of a screwdriver, secure the rail or accessory down and you are good to go. Installation is quick and easy. You never have to adjust anything on the underside of the handguard. The complete system is sleeker and more slim-lined than traditional mounting systems.

Kincel’s goal in “developing” the system was to have it become an industry standard. Therefore, he made the schematics an open source, so any manufacturer could create its own mounts, rails and accessories that work with the KeyMod handguard.

The KeyMod handguard has a 1913 rail along the top of it already, however, you can purchase additional KeyMod rails to add to the side or bottom of the KeyMod handguard. The strong attachment of the KeyMod accessories to the KeyMod handguard are unaffected by recoil and optics have an excellent return to zero capability when detached and reattached.

Rifles with this handguard and rail system are being produced by CMMG, Knight’s Armament, Primary Weapons Systems, Bravo Company, Spikes Tactical and of course Noveske—to name a few. Strike Industries have made them for the AK-47 and Mark Krebs of Krebs Custom Guns has made a KeyMod system for Saiga rifles, with more rifles expected soon.

New rail systems don’t just spring out every year and start a new industry standard. Weaver rails were all we had until 1994 when the Picatinny Arsenal—a military research and manufacturing facility— developed the Picatinny system. The Picatinny rail is now an industry standard on all semi-automatic, tactical-style, military rifles and some handguns.

Both Picatinny and Weaver rails incorporate a system of raised ridges with spacing slots in between. To mount an accessory to either, you slide the optic, grip, bipod or other gear onto the rail and then secure it using tools.

The 1913 rail has strict dimensions. The locking slot on the Picatinny rail is 0.206-inches wide and the spacing of slot centers measures 0.394 inches. In contrast, the Weaver rail’s locking slots measure 0.180-inches and have no consistent measurement in the slot center spacing. Therefore, Weaver mounted accessories will fit Picatinny rails, but Picatinny mount accessories will not fit always fit Weaver rails.

Needless to say, it took a very long time for the industry to switch from Weaver to Picatinny. We will have to wait and see if the KeyMod mounting system catches on. Currently, there are not many accessory offerings that fit the KeyMod system. Perhaps on the rifle we purchase to celebrate our retirement. Only time will tell.

Do you have a KeyMod rail system? What do you think—fad or the future? Tell us in the comment section.

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Comments (32)

  1. New to AR and bought onw with Keymod rail without knowing the difference. It’s okay, but trying to find a hand grip for the rail presents a challenge. I think I must get a short piece of Pic rail for the Keymod, then get a hand grip. Is that right?

  2. Like it.
    But you cant buy
    Anything for it.
    In canada anyways
    I’m trying to get a couple rails ordered threw
    Vltor witch they don’t ship to canada dealers only. But they are trying to help me out and get some rails sent over.
    Your left with putting a picitinny rail on anyway.
    The only good thing is you can take them off if you want witch makes the gun lighter witch makes them easier to sell.

  3. I just installed a YHM keymod hand guard on my last M-4 build. I Love the versatility of this system. I have no clue why anyone knock this. It gives me the chance to put an attachment point where ever I need it, but doesn’t flood the guard with a bunch of rails that I’ll never need. I doubt that I’ll ever use a quad-rail again.

    1. How do you figure it’s a fad? All of your high-end AR manufacturers are using the system and all of the other mass produced AR companies are starting to offer the system on some of their rifles as well. It is used by a large percentage in the competitive shooting community. It’s lightweight and not cumbersome like the other systems… I hate to tell you Steve, but the system is in it for the long haul…

  4. It’s interesting that most of the comments that were posted here are over a year old now. I wonder how many of the Keymod haters/doubters that posted here have had a chance to get their hands on a rifle with the Keymod hand guard on it and really gave it a try? It’s an incredible and very innovative system that is backwards compatible just as the Picatinny system is. In an age where there are so many AR type of competitions out there, its all about shooters making rifles that shoot fast and accurate. The shooters are also looking to make their rifles as light and strong as possible, which explains all the titanium/magnesium/carbon fiber parts that are hitting the market. The Keymod system is light, its strong and it keeps all the accessories closer to the hand guard making it easier to handle and maneuver the rifle. I’m sure if most of the people who knocked the Keymod system would really try one with an open mind they will see how much more advantageous the system really is.

    1. Yep sure do, it matches the one on my new build. It is a Seekins Precision MCSR V2 Mod Rail, you can see Seekin’s logo between the two sets of bolts that attach the hand guard to the upper. Their iRMT-R upper has the hand guard mounting nut integrated permanently into the upper to strengthen it. But you can also buy their Bar/MCSR mounting nut that can be added to any upper which will enable you to use their hand guards. Seekins makes great products, everyone that sees my hand guard loves it.

  5. This system is a definite improvement over a quad-rail. Modularity allows flexibility and a better balance of form and function. The negative opinions, I’ve noticed, including some idiot who bashes capitalism for producing choices and competition for him and is welcome to get the @#$% out of my country, are being written by people who haven’t used the system and don’t understand it. You add only what you need or want and don’t have to lug around anything you don’t. Want a side mounted light? – add a rail and mount your light. Don’t want a light? – don’t add the darn rail and don’t mount frikken the light.
    This system is durable, flexible, simple and effective. It’s much more comfortable than quad-rail; you can operate just fine without wearing gloves and there are no superfluous surfaces which require rail covers either, which keeps weight down. For all the Army bum-shots who take five mags to score a hit, it provides ample air flow for cooling. For my Marine Corps brethren, it looks as good as we do while we’re doing our thing.

  6. If that’s an AR type rifle in the photos, how would it apply to other type weapons? There are a lot of guns out there, besides that style of weapon, which now use the 1913 type rail, or possibly could. I have a Reminton 510 and 511 that I wish I could scope. I’m not sure about this new system according to the photos, but I think I’ll try to keep an open mind, at least until I get to see it in person, or see more applications of it.

  7. I agree that too much Picatinny IS TOO MUCH! I used to have a quad rail on my “M4”, but replaced it with a smooth tube, but added short sections of Picatinny in strategic locations for a light and/or laser. The sections are made of composite plastic, and are more than strong enough to hold what I attach.

    The quad-rail forearm needed ladder & panel covers to prevent catching, grabbing, cutting of things that came in contact. It was also very FAT.

    Still KISS.

  8. I’m not sure what the detractors of this system don’t like. As I understand it one can mount a rail section only where one needs to mount an attachment if there isn’t a direct keymod mount. Seems pretty smart to me. Why have a quad rail all the way if one is only using a small portion of it? Am I missing something?

  9. I recently picked up a Noveske upper for a build. I was immediately struck by how thin and light the thing is, despite the full length Picatinny rail on top. As I was putting the rifle together, the first thing I did, out of habit I think, was start bolting Picatinny sections to it “for future use” and, whoa, what a mistake! Soon my project rifle started to get very heavy. So I regrouped, stripped off the Picatinny rails I wasn’t using, and replaced them with Noveske polymer covers. I found a KeyMod flashlight mount and I was (almost) in business. I say almost, because I had to add a Picatinny section back on the bottom to support a vertical foregrip, since I’ve not found anyone making a KeyMod version yet.

    The result is an AR15 with a free-floating barrel which is surprisingly light and far less bulky than quadrails, or even Magpul. The rifle is a dream to carry and use. I’ve not had it long, but it feels like it’s going to hold up well to every day abuse in the field. The Noveske NSR handguard is far thicker and more durable than it looks in pictures.

    The downside, at this point, is the lack of maturity of the system and the ecosystem around it. As I mentioned, adding a vertical foregrip, or a Magpul angled grip, requires the addition of a Picatinny section, as do a number of lights (Streamlight TLR, etc.) and other accessories designed for 1913 rails. The good news is that Picatinny rail sections can be added in a few seconds and they’re rock solid once they’re mounted.

    The youth of the system can also be seen in the currently spotty availability of the few accessories at ARE being produced for it. The only polymer handguard panels being offered are from Noveske, and the company has had a hard time keeping inventory available. Short Picatinny rail sections are also hard to come by. I realize that the economics of trying to set a new standard can be challenging, and Noveske has had a particularly trying year with the tragic death of their founder. Still, if they want KeyMod to catch on as a standard, they’re going to have to keep parts in stock.

    It has been encouraging to see other manufacturers beginning to offer KeyMod accessories. If the trend continues, KeyMod is likely to see wide adoption pretty quickly. Rifles that use it can be made lighter and easier to handle and customizing them is, literally, a snap. It’s important to note that KeyMod isn’t likely to replace the Picatinny 1913 rail. I don’t think that was the intent. But I believe it will replace heavy, bulky quadrail systems that have been the rage of late.

    If you’ve not seen the KeyMod system, I encourage you to take a look at it.

    1. I have a Seekins Precision AR I just built and it has that exact keymod hand guard, its an awesome hand guard. There is no sharp corners to catch on anything and like mentioned above, you don’t need to use gloves on it.

      As for your vertical grips comment, there are several companies out there that make the vertical grips that fit the system. And you DO NOT have to add a Picatinny rail to mount them. There are angled grips as well.

      Bravo Company –

      Fortis –

      Samson –

      There is just as many accessories for this system as there are for the older systems. You just have to look for them, Google is ones friend 🙂

      Harris bipod mount –

      Hand stops / swivels –

      Sling Mounts –

      Flashlight mounts and various other mounts –

      And then you have as you said, Noveske, Midwest Industries, MidwayUSA…

      The only difference is that you can’t find all the stuff at one super store like you can for the Picatinny stuff.

  10. @RPK, I don’t think people necessarily fear change, but they shy away from change just for the sake of change, or just for profit. We have a very fine, robust and workable system in the Pic rails. They are backward compatible and very solid. For the Keyhole slots to take over, it is not sufficient just to be different. They have to show a compelling reason that they are better than the current system. Note that I said COMPELLING, not just a slight advantage. People have a lot invested in the current system. I might be willing to change, but they will have to show me a REAL reason to do so.

    1. I have two AR’s, one with each system. The Keymod system beats the Picatinny system in a lot of ways, the biggest being weight. The Keymod hand guard weighs about half that of the common Picatinny hand guard. With the Keymod system you are able to mount the accessories closer to the hand guard eliminating a lot of the Picatinny’s bulk. And another one of the big advantages the Keymod system has is that it doesn’t have all the sharp edges that the Picatinny system has. So one, you don’t have to add all the plastic covers to make the Picatinny rail smooth and snag free. And two, the overall diameter of the Keymod rail is smaller which makes it easier to handle.

      Just an observation from a user of both.

  11. Inherently, people fear change. The current system has become the industry standard. The majority of after market parts are manufactured for this system. I know having spent cash to modify my weapons with a rail system will probably deter me from upgrading to anything different, at least in the near future. But, as with everything else, only time will tell. If I see it, it appeals to me and I have the money on hand, I’ll take it for a test drive.

  12. I like the new keymod system, I like it because the noveske pictured is a free float tube and lightweight. It dislike full quad railed hand guards. They are big and heavy, most have sharp sharp corners so gloves are needed, then you need rail covers which adds even more weight. Since there aren’t a ton of accessories for the new system yet, you can just add rail sections as needed, just like 90% of the other free float hand guards on the market right now, and the key mod will be less weight if you don’t add rails and use key mod accessory mounts (when/if they are available), and you will also be able to have accessories mounted closer to the weapon without rails adding width to the rifle. Key mod is also way easier to machine than quad rail hand guards also I would imagine.

    I do feel that the key mod system won’t work as/ or ever replace the top mounted picatinny rails on most/all modern rifles.

    1. You hit all the right points Jared 🙂 I just did a build using a lot of parts from Seekins Precision, the manufacturer of the hand guard in the top picture. And I have another AR with all Picatinny rail items, the Keymod system beats the Picatinny hands down in all the ways you mentioned.

      And you are right, the Picatinny rail at the top is the best mount for scopes and quick release mounts so it definitely won’t be replaced any time soon.

  13. This is merely a system used to generate more revenue from already money hungry people. It doesn’t solve or fix anything as far as I can tell. They are making you buy more mounts to put pict attachments on it. Seriously, its just making a middle man between you and the accessories. Try a durability test and I bet pict based rifles will last longer which is what the military needs if know the whole idea of something being made for grunts (grunt proof??). This is no different in how Howard leight will charge me $35 for a pair of non electronic headphones but I can go to home depot and get the same decibel rating for my ear pro for less $$$. This is why I hate capitalism and creation. They can be of the devil at times and great at others.

  14. I can’t say that I really see the point in it, other than it looks kind of cool. The picatinny rail system is secure, fast, and easy. This new thing looks more like an overcomplication of a problem that has already been solved. I just see this thing being a frustrating failure that looks good, and that’s about it.

  15. It seems logistics problems are solved by just making segments of rail fit to the keymod and then mount whatever you need. The same as the Magpul MOE system. After all, keymod is just a copy of the MOE system but with denser mounting design. I wouldn’t call it revolutionary since magpul already pioneered this feild, but I would say it is not going away, after all after magpul now noveske is making it too!

  16. That doesn’t look nearly as robust as rails. Looks too easy to knock out of shape. Then what? And looks a pain to machine for the top of the rifle. So, we have to have mounts for the side AND top? They may be able to force this down the military’s throat (but I hope not) but if we don’t buy it, it will go away.

  17. Having been associated with the Picatinny Rail system concept since its inception in the early 80’s when I was stationed there, and its manufacture since 1994 and I can say without reservation that none of us knew beforehand or early-on how far it (and the modular forend/weapon system) would go or how it would evolve into so many other innovations more than 30 years later. So give the KeyMod (and our innovative weapon/accessory developers–both military and civilian) a few years to get this ball rolling…I think you will see a total transition, or at least several hybrid combinations.
    The KeyMod is simply more efficient across the board, I mean look at a M16A4 Rifle with the rail forend (M5 RAS). It has 106 Picatinny Rail accessory grooves between the upper receiver and the forend; of which less than a dozen are ever utilized–even on a heavily accessorized forend (i.e., bipod, flashlight, laser, flip front sight, etc.

  18. Just received a CMMG piston upper with the KEYMOD rail system and it makes moving or attaching 1913 rails very simple. This hand guard fits my short fingers because of it’s smaller dia. If the industry will provide accessories such as lights and lasers I think it will catch on faster, if not the ease of installing and moving the 1913 rails will make it worth the money.

  19. Suzanne,

    That was my point above. Picatinny rails were a safe bet because they could fit (most of) they existing accessories, and still fulfill the specs the military wanted. This new system is starting out from ground zero and is going to require sellers to carry a whole new set of accessories in addition to what they already carry. And you know as well as I do the shooters are a stubborn lot. You will have to convince them of overwhelming superiority to change to a new system. I like them, but think they should be eased in slowly and perhaps include compatibility with Pics and Weavers at first. Also, do you know if anyone has tested them for durability and tightness under shooting conditions?….Thanks for the article…

  20. Bill,
    The owner of the gun in the picture loves the KeyMod system. The only problem I see with it right now, there are not many compatible accessories yet. And no, that is not my blue nail polish. Unfortunately, I have not had a chance to shoot that particular AR-15 yet.

  21. I agree with keeping it simple. I only have two weapons with rails, and I don’t as yet utilize them. We have too many choices in this world. However, being as how those keyhole slots are recessed as in the picture, I can see where they could be an advantage. You can see in the photo, the person’s hand grasping them, that the concept doesn’t comprimise comfort. (That’s not your blue nail polish, is it Suzanne?) But then, I couldn’t see the point of “Molle” at first either. Time, and tasteful innovation will tell.

  22. Great idea, but changing the momentum & popularity of the 1913 Picatinny rail will be difficult. The main reason: The Military. Both the Military & commercial markets have adopted the 1913 in every aspect of weaponry – from .22 rimfires to the Browning M2 .50 caliber machine gun.

    Also, the industries have adopted the 1913 system for the accessories – from scope/sight/light mounts to sling & bipod mounts.

    Quite simply the KISS (Keep It Simple, Stupid) principle works with the 1913. It works, it is simple, it is strong, it is the “standard” in accessory-mounting systems. Look at the Molle system, too: simple & effective, and becoming popular.

    I love it when great ideas come along, and saddened if/when they fall along the wayside. Perhaps the new concept will catch on elsewhere in Military & commercial applications.

  23. Picatinny rails were adopted faster because they were backward compatible with Weaver accessories. Perhaps the slot lock system would be more quickly accepted if it replaced only the slots on the top of the rail and left the current profile unchanged. Then, current accessories (that mostly mount to the sides of the rails, would still work. Just my 2 cents…

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