M-LOK vs. Keymod?

[easy-e]

Well, considering that I *am* a "rifle virgin"* and still in planning stage on a first build... I'm trying to make sure I plan a build that most of you guys wouldn't mind owning, and I figured if *I'm* intimidated by the variety of parts and options out there there are probably others who could benefit from the Q&A too.

I debated this a lot and decided on buying a complete rifle. I had pretty much convinced myself I wanted a BCM and then one showed up here in the classifieds and I jumped on it.

BCM only does Keymod so by deciding on that manufacturer I also decided on the type of rail. I had always wanted to try one of the Magpul angled foregrips but they won't work on Keymod without modification or a Keymod->MLOCK or Keymod->Picatinny adapter. The accessories I do have lock in SOLID. I'm very happy with Keymod.

I probably will not build one from scratch and I'm not in the game to own a ton of guns. If I wanted something very cheap or was building a target rifle I'd strongly consider it. I was looking more for total reliability out of the box.

According to this report M-Lok is outselling Key-Mod 3-1.
M-LOK Outselling KeyMod about 3 to 1 - The Firearm Blog (http://www.thefirearmblog.com/blog/2016/01/28/m-lok-outselling-keymod-about-3-to-1/)

I had read this thread and this article was one of the only reasons I seriously considered M-Lok instead. Magpul has the ability to shift the market. Both systems seem great but it'll be interesting what's still around in 2, 5, or 10 years and what new stuff people have come up with.

 

[Quartermaster]

Keymod fits in like... A key. M lok mounts on magpuls polymer handguards and stocks will chew up, scar, and forever damage the mount. It's not intuitive, it doesn't index itself, and you can't assure the mount is lined up properly without visually verifying the underside of the mount. Keymod is simple, works across countless industrial applications using the same mounting system for storage, equipment, and machinery. M lok has the power of magpul, and the support of their fanbois.

 

[old11bravo]

Mlok'er guy here. Soo much more pleasing aesthetically and every bit as functional, if not more than the K stuff.

 

[etrain16]

I like Keymod but wish there were more plentiful options on the market, such as Magpul items - likely that won't be happening though. I'm about done with pic rails though.

 

[partsed]

Next rifle I build will have Keymod on it. While Magpul has great stuff, my son and all of his friends are all about the M-lok system and I am not... Stubborn I guess..

 

[Joe Link]

I still can't seem to decide. I'll probably end up with both

 

[Joe Link]

Be careful of cheap M-Lok handguards. I bought one and then discovered that it wasn't machined on the inside properly. There actually is a spec, but some of the Chicom fabricators don't seem to be able to look it up. Took it back to the LGS, and they were pretty ticked off at the supplier. Immediately offered me a cash refund.

Which brand was the handguard?

 

[Diamondback]

Each has its virtues... for example, if you're aiming to reduce weight Keymod seems to usually run a few ounces lighter than M-Lok. "Ounces are pounds and pounds are PAIN"... (Yeah, yeah, says the guy whose lower alone weighs as much as a complete M4.)

 

[CHLChris]

Picatinny quadrails are extremely uncomfortable to use for your support hand. Yes, you can add rail covers, but then your handguard becomes extremely girthy. The moment I can commit the money, I'm gonna switch to M-Lok. One aspect to consider is that KeyMod is slowly going the way of unpopularity. Therefore, over time, M-Lok is going to surpass KeyMod and will have more and more accessories made for it.

To me, concerning popularity, it seems to me that KeyMod/M-Lok is somewhat analogous to 40S&W/9mm. The 40 is still really great, still has a lot of proponents, and probably will not disappear anytime in the near future...but 9mm is gaining acceptance and developing ubiquity.

No Picatinny quadrail
Maybe KeyMod
Yes M-Lok

 

[Joe Link]

Picatinny quadrails are extremely uncomfortable to use for your support hand. Yes, you can add rail covers, but then your handguard becomes extremely girthy. The moment I can commit the money, I'm gonna switch to M-Lok. One aspect to consider is that KeyMod is slowly going the way of unpopularity. Therefore, over time, M-Lok is going to surpass KeyMod and will have more and more accessories made for it.

To me, concerning popularity, it seems to me that KeyMod/M-Lok is somewhat analogous to 40S&W/9mm. The 40 is still really great, still has a lot of proponents, and probably will not disappear anytime in the near future...but 9mm is gaining acceptance and developing ubiquity.

No Picatinny quadrail
Maybe KeyMod
Yes M-Lok

From my limited perspective, this is how I see it. I honestly think KeyMod might be the better tech, but it's hard going up against the 800lb gorilla that is Magpul.

 

[FireArm]

My observation is that M-lok is cheaper, not in quality but in price.

 

[titsonritz]

M-LOK is backwards compatible with MOE accessories and is more versatile and easier to manufacture than either MOE slots or Keymod.

M-LOK just updates the MOE standard with a TDP that is open to all manufactures and was designed from the outset to be utilized on metal, polymer or carbon fiber mounting surfaces.

M-LOK uses a flat nut that is suitable for polymer, metal and carbon fiber mounting surfaces.

M-LOK works over a wider material thickness range than Keymod.

M-LOK is a true direct attach system so a line of accessories mounted next to each other do not need to be slid off to remove just one piece.

M-LOK has better recoil/impact support than Keymod.

M-LOK uses a larger bolt and has greater direct surface contact than Keymod resulting is greater pull out strength (a single MLOK mount exceeds 300 lbs in all materials). A Keymod slot if very thin at fastener contact surface, reports of torn/deformed slots are not uncommon.

M-LOK accessories are multi directional (can be mounted forward or backwards).

M-LOK has a uniform internal edge that can be generously chamfered allowing a better feel on the hand than Keymods 45 degree under cuts.

M-LOK can use any of the millions of MOE accessories already fielded via an adapter plate.

M-LOK slots are much lower cost to manufacture than Keymod resulting in lower cost to consumers.

M-LOK nuts are much lower cost to manufacture than Keymod resulting in lower cost to consumers.

M-LOK bolts are commonly available (user replaceable) and allow more torque to be applied than Keymod.

M-LOK slots requires no special CNC cutters or complex injection molds to manufacture an undercut like Keymod resulting in lower cost to consumers.

M-Lok definitely has a higher torque rating. I think it was 35 in/lb for metal. If you torque keymod to 35 in/lb you'll deform every rail I have tried it on. Anyway, higher torque rating also means less chance to loosen up. But if you aren't using some thread locker, regardless of the specific interface, you're doing it wrong.

Keymod does allow for a slightly lower QD mount than MLOK and is almost flush on the inside of the tube (that might affect those mounting suppressors internally within a small freefloat handguard or when mounting accessories at the gas block location)

There is more than enough room for both but I ended up going with MLOK for several reasons aesthetics, more adjustable and is supported by the largest manufacturer of accessories. Now if I want something tough as nails, still the Picatinny. Crying about the cheese grater? Toughen up or at least get some gloves and/or rail covers.

 

[titsonritz]

Cheaper keymod rails might be out of spec there for attachments won't lock in place. Haven't seen that as an issue with mlok. Had that issue with a $150 rail I bought. Went online saw alot of people ran into that with hand full of different rail makers.

Be careful of cheap M-Lok handguards. I bought one and then discovered that it wasn't machined on the inside properly. There actually is a spec, but some of the Chicom fabricators don't seem to be able to look it up. Took it back to the LGS, and they were pretty ticked off at the supplier. Immediately offered me a cash refund.

What do you expect from cheap crap, that has nothing to do with Keymod or M-Lok.

 

[Joe Link]

M-LOK is backwards compatible with MOE accessories and is more versatile and easier to manufacture than either MOE slots or Keymod.

M-LOK just updates the MOE standard with a TDP that is open to all manufactures and was designed from the outset to be utilized on metal, polymer or carbon fiber mounting surfaces.

M-LOK uses a flat nut that is suitable for polymer, metal and carbon fiber mounting surfaces.

M-LOK works over a wider material thickness range than Keymod.

M-LOK is a true direct attach system so a line of accessories mounted next to each other do not need to be slid off to remove just one piece.

M-LOK has better recoil/impact support than Keymod.

M-LOK uses a larger bolt and has greater direct surface contact than Keymod resulting is greater pull out strength (a single MLOK mount exceeds 300 lbs in all materials). A Keymod slot if very thin at fastener contact surface, reports of torn/deformed slots are not uncommon.

M-LOK accessories are multi directional (can be mounted forward or backwards).

M-LOK has a uniform internal edge that can be generously chamfered allowing a better feel on the hand than Keymods 45 degree under cuts.

M-LOK can use any of the millions of MOE accessories already fielded via an adapter plate.

M-LOK slots are much lower cost to manufacture than Keymod resulting in lower cost to consumers.

M-LOK nuts are much lower cost to manufacture than Keymod resulting in lower cost to consumers.

M-LOK bolts are commonly available (user replaceable) and allow more torque to be applied than Keymod.

M-LOK slots requires no special CNC cutters or complex injection molds to manufacture an undercut like Keymod resulting in lower cost to consumers.

M-Lok definitely has a higher torque rating. I think it was 35 in/lb for metal. If you torque keymod to 35 in/lb you'll deform every rail I have tried it on. Anyway, higher torque rating also means less chance to loosen up. But if you aren't using some thread locker, regardless of the specific interface, you're doing it wrong.

Keymod does allow for a slightly lower QD mount than MLOK and is almost flush on the inside of the tube (that might affect those mounting suppressors internally within a small freefloat handguard or when mounting accessories at the gas block location)

There is more than enough room for both but I ended up going with MLOK for several reasons aesthetics, more adjustable and is supported by the largest manufacturer of accessories. Now if I want something tough as nails, still the Picatinny. Crying about the cheese grater? Toughen up or at least get some gloves and/or rail covers.

Well this makes me feel better

 

[dwaineshort]

What do you expect from cheap crap, that has nothing to do with Keymod or M-Lok.

Not really sure if you call a hundred and fifty to two hundred bucks cheap?

 

[wired]

Ive got both and dont really see one being significantly better than the other with a slight edge going to the keymod just because its faster and a little easier to attach stuff I dont attach often. Both are better than those cheese grater rails although the rails are faster than any of them ( but they still suck ).

I dont drink Kool Aid so take my opinion for what it is ...Mine.

 

[Pandaz3]

I have both and rarely accessorize, so it doesn't really matter a whole lot. I think you can buy most things for either that I would want or use

 

[Mikej]

Cheaper keymod rails might be out of spec there for attachments won't lock in place. Haven't seen that as an issue with mlok. Had that issue with a $150 rail I bought. Went online saw alot of people ran into that with hand full of different rail makers.

I purchased a rifle from Curt's with the key-mod hand guard. Small diameter and not "Cheese Grater". Very comfortable. The problem is I went to attach sling with a Troy swivel. The key-mod mount went on the rail fine, but the swivel piece wont go in the mount all the way because the hole in the rail is too small.

Question: Are there two sizes quick release swivel mounts? Or is it as @dwaineshort says above, and I'm screwed and needing to buy another rail?

 

[Boboclown]

Keymod rail adapter and a rail sling mount if you don't want another handguard.

 

[WillNotComply]

I purchased a rifle from Curt's with the key-mod hand guard. Small diameter and not "Cheese Grater". Very comfortable. The problem is I went to attach sling with a Troy swivel. The key-mod mount went on the rail fine, but the swivel piece wont go in the mount all the way because the hole in the rail is too small.

Question: Are there two sizes quick release swivel mounts? Or is it as @dwaineshort says above, and I'm screwed and needing to buy another rail?

Is it a Diamondhead? Long story, but they have had a bad run. My LGS is working with both Stag and Diamondhead on this. I can update more next week when hopefully this is all resolved. I needed to go to my LGS after the lack of response from Stag and, especially, Diamondhead. Talk to whomever sold you the handguard. My LGS found two in his stock that were out of spec. Stag sent him two replacements, both out of spec.
Good luck!