M-Lok vs KeyMod. What are the Pros, Cons and the best choice?

M-Lok vs KeyMod. What are the Pros, Cons and the best choice?

Posted by STNGR USA on Mar 4th 2019

Today is a great time to be around if you’re a person who loves firearms. Even more so if you’re of the inclination to modify your guns to your liking. Modifying your firearms to fit your needs, likes and body type is nowhere more apparent than in today’s modern sporting rifles. We have at our finger tips a plethora of choices in optics, barrels, muzzle devices, butt stocks and on and on. But today we’ll focus our attention on handguards or fore ends. We have the ability with these to mount various accessories that help accomplish our intended purpose with the real estate provided to us with these rails. Finding the right handguard length is important, but that is for another post. Gone are the days of hose clamping and duct taping lights to the hand guard. Those days started waning with the invent of the picatinny rail. The Picatinny rail allowed us to mount optics, lights, lasers, bi-pods and a whole host of other spiffy do dads onto our rifles. By 2007, the legacy Picatinny rail was being eyed for replacement by several companies. With VLTOR Weapons Systems’ Keymod making its entry to the field in 2012, and Magpul’s M-LOK debuting in 2014.

Why should we care about M-LOK and KeyMod? For one true innovation can often times be at a snail’s pace in the firearms world, and these happened independently of each other and in quick succession. More importantly they’re both noticeably lighter than the Picatinny rail. While the Picatinny rail does an outstanding job accomplishing the mission it was created for, it does so at a cost in weight. With the design allowing mounting of gear anywhere along the handguard it gives you space to play with, but after you’ve selected your spots, the rest of the sections go unused beyond cheese grating your ungloved hands should you not cover them. Both M-LOK and Keymod address this issue by lightening the rail up tremendously and creating recessed openings that are used to mount accessories via their respective mounting hardware. So let us dig into them both a bit.

M-LOK

M-LOK is the brainchild of Magpul Industries. It being a replacement for MOE line of mounting equipment, the M-LOK addressed some of the issues that came up with MOE, namely having to access the rear of the panel/rail section in order to mount properly. The new M-LOK utilizes, t-slot nuts backed, held tight with your choice of thread locking fluid. M-LOK made its entry in 2014, with Magpul retaining the free licensed, in their words insuring that others wishing to use it maintain quality of their mounting system.

PROS

  • Sturdy: In 2017 US SOCOM conducted testing to compare both Keymod and M-LOK. This testing revealed through quite a bit of abuse that the M-LOK would hold up to well beyond they’re requirements. With the testing revealing accessories staying attached 100% of the time during drop testing.
  • Magpul Retains the free license: Now hear me out here, this is solid plus in my eyes. Magpul allows other manufactures to use their design, so long as they acquire permission. This allows Magpul in theory to insure that quality throughout the various manufacturers remain up to par. Meaning you get solid equipment.
  • Wide Aftermarket support: This is pretty straight forward, there are tons of people making no only rails, but things that mount to it.

CONS

  • Difficult to mount accessories: While Magpul improved over their MOE, the T-slot nut based mounting hardware can still be a pain to mount. From personal experience, I still find it easier to remove the rail, to mount things to it, at least during the initial threading of the bolts.
  • Heavier: When in comparison to the Picatinny rail, the M-LOK rails are still far lighter. But when you look at them in comparison to the Keymod, they lose. Even if it’s only by a fraction of an ounce or two.

KEYMOD

KeyMod has it’s begins with a collaboration between VTLOR and Noveske Rifleworks. Hoping to do away with the weight associated with the Picatinny rails. Instead aiming to have a lighter rail, with users choosing where to directly mount accessories, using KeyMod accessories, or small Picatinny rail sections for legacy equipment. KeyMod gets its name from the key hole like appearance. After release of the new mounting system, the specs were released open source for any who choose to use it freely.

PROS

  • Easy to install accessories: The KeyMod system is basically idiot proof. Unlike the M-LOK, the KeyMod indexes easily. With little to no room for false positives that everything is seated properly. Another bonus, it doesn’t require liquid fastener on the nuts and bolts.
  • Open Source Specs: VTLOR released the technical specifications to the world for all to use. While some caution and some research should be done, the ability for anyone to use the specs to create a rail has led to some innovations that can be rather ingenious. Like the through hole portions being changed up to allow the end user the ability to use any of the “key holes” as a mounting location for a QD sling mount.
  • Easy Return to zero: Because of the design, with no fore or aft movement within each mounting locations, throwing accessories, such as IR lasers, visible lasers and others requiring a zero is much more simplified. Needing minimal re-zeroing when reattached. Unlike the M-LOK rail where there is quite a bit of wiggle room within each of the slots.

CONS

  • Easier to break: Now let me clarify. When SOCOM did their testing of KeyMod, they beat the tar out of the rails, far more than most civilian side shooters could dream of. Finding that accessories mounted properly to the KeyMod were more likely to separate from the rail; for example in the drop test, an astounding number of 66% of the time a mounted flash light would tear clean of the handguard. However you probably won’t be thrashing your rifle near as much as SOCOM does.
  • Accessories: While there are still a ton of things being made to mate up with the KeyMod, those numbers aren’t as prevalent as the ones seen with M-LOK, primarily due to the perceived weakness revealed by SOCOM’s testing of both.

Who’s the winner you may ask? Well in my book it’s the M-LOK. The wide aftermarket support, overall survivability of the rail and any attached, appeal to me. I’m a guy who tends to like to over engineer things, and the M-LOK fits that thought process in me.