Is M-LOK better than Picatinny?

Attachment systems on firearms are a vital part of any firearm, not just the AR platform. The receiver of a rifle has an attachment system, an M249 handguard is now an attachment system, the bottom of a pistol frame is an attachment system. They all serve the same purpose though, allowing the user to put something on the gun that hopefully..doesn’t move or fall off. In this article, we will look at the origins and differences of Picatinny vs. M-LOK.

The uses of Picatinny has went from the AR platform to our machine guns as well. Notice the front rail on this M249. Soldiers now use it to mount PEQ-15’s and other accessories. Photo: FNAmerica

So where does that put us? Well, it puts us in decades of dispute as to “what attachment system is better”. Not only us, but the military joined the fight as well. These two very trustworthy attachment systems have allowed both civilians and the military to attach optics, lasers, and lights onto their firearms without them moving. We will also go over the importance of knowing your specific attachment system and lay out some Gunsmith tips and tricks to mount your accessories on these systems properly.

Don’t worry, after you read this article, you too can enter yet another firearm debate. Yay!

Rail systems have definitely come a long way and I don’t foresee changes stopping any time soon. Whether it is an older system such as Picatinny or a newer rail system such as M-LOK both are very important to the technological advances we have within our firearms.

Origins and Current History

As far as what came first, the Picatinny mounting system, later standardized by the Military as MIL-STD1913, came much, much before the Modular Lock (M-LOK) system from Magpul. However, both are still being used heavily today. The Picatinny mount, named after Picatinny Arsenal, has become an open source and Magpul’s M-LOK has allowed for a license to be obtained from Magpul if any other companies want to use it. Freedom in design allows for vast improvements and advances in firearm engineering, so thank you for that.

Picatinny

Now for chicken and the hen..what came first: C. Reed Knight Jr.’s invention of the Knights Armament Quad Rail or Picatinny from Picatinny Arsenal? The story of how the Knights Armament Rail Integrated System (RIS) influenced the Government to invent Picatinny is here, and it is quite entertaining and eye opening. You decide for yourself. Focus on the part where Mr.Knight allowed military folk to go from taping a flashlight onto their gun with duct tape, to giving us a quad rail and modular methods to attach foregrips and lights.

Anyway..no matter what came first, the very heavily used Rail Adapter System (RAS) from Knights Armament now has the Picatinny interface.

That Picatinny interface being given to us officially by Picatinny Arsenal and engineered by Gary Houtsma. More information on that here.

M-LOK

The origins of M-LOK go back to 2007 with the Masada Concept Rifle. This rifle, designed by Magpul, featured three slots in the front that allowed for the mounting of an accessory. This then leads to Magpul’s MOE line, which is still a very popular line of lightweight handguards. However, the M-LOK design wasn’t quite there due to needing to take the handguard off to mount anything to it. Yikes. Now, we have M-LOK, standing for Modular Lock. The rail slot shapes were adjusted and squared off and the mounting hardware was also changed a bit. More information on the history, specs, and how to install can be found here in a Magpul Press Release on M-LOK uploaded online by Giessele.

M-LOK is now being produced by almost every large firearm manufacturer and is being adopted by various military and Federal entities.

You will see in our best AR-15 handguards article we suggest both M-LOK and picatinny options.

Picatinny on top, MLOK on bottom

Designs and Pro’s/Con’s

The design for the two systems are very different. You will often be able to tell right away when looking at a hand rail or an accessory that mounts to a rail which system that product is designed for.

Picatinny

The picatinny mounting system is a slotted and clamping type of system. The rail has individual slots often marked with numbers. That way, you can remember where your accessory was mounted if you need to take it off and remount it. Your accessory will have a bar on the mounting plate that fits into those slots. On the side of the mounting plate, there will also be a locking/clamping type of bar. Place your accessory in your chosen slot and tighten down the locking screw, which then tightens the clamping bars to the side of the rail. Therefore, not only is there a bar accepting recoil but also clamps on the side of the rail.

• Common – Picatinny is still everywhere, even though it is forty years old. Look at a receiver of any AR platform or the newest hand rail of a M249, picatinny. Look at a lot of lasers and lights that are meant to mount on the side of a rifle. They will often have a picatinny plate already on the laser.
• Quick Detach Options – Picatinny is prevalent in allowing quick detach accessories, such as accessories with a tensioning lever, to make it easy to take on and off of accessories.
• Versatile – Now Picatinny is even being used in the archery world, to mount sights to bows.
• Simple – It is super simple to use. Simply fit the mount into a slot and tighten.
• Strength – The system is also strong. Get a dent or hit to the rail and your accessories should still hold. Why else would they would still use it as the main system for mounting an optic? Something that needs to hold zero always.

• Nock Offs – It is also everywhere, which means that some company may not be following proper MIL-STD1913 specifications. The more slop in those specifications means more movement to your accessory in the middle of those slots.
• Height – It also pushes your optics even higher and more outwards due to needing that rail space that the sides of the rail clamps onto.
• Bulky – it is pretty bulky. Wrapping small hands around a quad rail with picatinny on each side of the rail can be tough.
• Rough Texture – Picatinny slots can be like a cheese grater on your bare skin if left uncovered
• Heavy – All of the extra material that makes the rail system strong, also makes it heavy

Note: There is a similar design to Picatinny that is called “Weaver”. It is easy to get these two confused, however, they are different mounting surfaces. Ensure that if you are looking at a rail similar in nature to picatinny, verify which specification it actually is.

M-LOK

The Modular Lock System from Magpul is a bit more complicated, but still simple to use. The slots on the rail look like skinny ovals. A M-LOK mounting accessory now has two screws with a similar shaped type of lock nut. The lock nut stays on the screws at all times. Turn the screws so that the nut can fit through the slot. Now, turn the screws again so that the nuts are perpendicular to the slot. Now tighten. The nuts clamp onto the inside of the rail and tighten down your accessory as you tighten down your screws. Bam, your M-LOK accessory is now mounted onto the M-LOK rail.

Notice the design of the M-LOK in this photo. The two nuts are able to be turned onto the screws that they are placed on. Simply turn them so that they line up into the slot, then turn them again so that they are perpendicular to the slot and you can start clamping the nuts onto the rail.

• Negative Space – Alright I’m going to say it..negative space. Are you turned on yet? You should be, because this term is what will pop up in any google search you do on M-LOK due to being of such importance within Mil-Requirements when designing and delivering M-LOK. Really though, it is a huge pro. It makes rails much less bulky due to not having to add anything to the rail to make the system but instead, cutting out holes
• Weight – Less bulk also means less weight. Something that someone like myself, a small female with small hands and not as many muscles as you big boys, loves in a hand rail.
• Direct Mount – Accessories are able to be directly mounted to the rail, thus not adding any bulk to the accessory and ensuring that it stays tight to the rail.
• Slim – The more slots, the more places that accessories can be mounted. M-LOK allows for multiple different places for accessories to be mounted without adding the bulk of more material.

• Learning Curve – M-LOK is a little more difficult to get the hang of and there are more parts to lose. However, once you get the trick of knowing when to twist the screws so that the nuts latch onto the rail and how to pull up when tightening, ensuring that those nuts don’t move, it’s easy peasy. Just make sure you don’t lose a nut inside the gun..speaking for a friend..wink wink.
• Nock Offs – While all things M-LOK are supposed to be licensed as well, there are still some crap options out there, such as plastic rail sections and incorrectly sized M-LOK pieces. This can make installation a pain. Ensure that any M-LOK product you get has the M logo on it from Magpul and isn’t plastic. Just stay away from non-aluminum rail sections, you’ll thank me later.

The Importance of Knowing Your Locking System

So why do we care? Well, any type of accessory that you buy will need to be compatible with the system that you’re mounting it to.

Picatinny mounting plates on accessories are pretty easy to spot due to the clamping bars on the sides of the accessory. All of the above accessories are set up to be mounted to picatinny rails including the old school KAC foregrip.

Optics that are being mounted on the top rail are pretty easy considering most top rails of firearms are 1913 picatinny. At this point, you just need to decide the height of the mount of your optic that you want, and if you want it to be attached with a tensioning lever, screws, or locking lugs.

Other accessories get a little more tricky. For instance, some accessories that you buy if you do not buy an adapter will only be able to be mounted onto picatinny. Thus, if you have a M-LOK handguard, you will then need to buy a picatinny section and mount it onto your handguard. If you do find the same accessory in M-LOK, buy that. Direct mounting on anything is always better than allowing for two things to come loose.

“I remember being at Fort Benning one year, and I was there with a group of people, and this sergeant came up to me, he said, “You’re Reed Knight, aren’t you?” I said, “Yeah, I am.” He said, “I just want to shake your hand,” he said, “I train thousands of people here in basic training in the shooting skills, and every time I get a shooter that does not qualify, I can give them one of your vertical pistol grips, and they always qualify afterwards. That one piece of gear has made more difference in people qualifying in military shooting than any other piece of gear that I’ve ever seen come through here.”-Mr. Knight

quote about that foregrip from an Interview with Mr. Knight on SmallArmsReview

In this photo is both M-LOK and Picatinny. The Magpul Hunter Stock has M-LOK sections on the stock’s for additional accessories. However, I wanted a bipod that could easily be detached. To do that I purchased a Picatinny rail section and mounted it via M-LOK enabling the quick detach picatinny adapter to be mounted onto the gun.

Things such as bipods that you may want to become quick detach (QD) also create some issues. Depending on your bipod, you may need to buy a Picatinny or M-LOK adapter that is compatible with your specific bipod. Many of these QD adapters, such as this one from American Defense Manufacturing, will only release from Picatinny so another section may need to be bought. If you don’t care for your bipod to be quick detach, simply buy a M-LOK Bipod Mount such as this one from Magpul.

In simple terms, the three things that you need to know is, what mounting system is my handguard? What mounting system does my bipod currently attach to? What system do I want it to be attached to? At that point, simply input those terms into google and you should find information for it.

Tips for Mounting Hardware

• When mounting optics onto the top picatinny rail add some lubrication to the rail, this will help with friction and keeping the optic tight.
• Push forward (to the muzzle of the gun) on your accessory when mounting. This will help with recoil and keeping the accessory tight.
• Witness mark your screws. This means that after tightening everything down, take a paint pen and mark on the screws and your rail in a line. This will show you if anything moves before you lose your accessory in the grass or wonder why you aren’t hitting where your optic says you should.

The Magpul furniture for the Remington 870 also features M-LOK, because who doesn’t want additional stuff on their shotgun such as a light? Note the two white lines on the Magpul branded screws for M-LOK accessories. Those white lines are known as witness marks. If those white lines no longer match up over time I know that something has come loose and the screws have shifted.

• If you are using a tensioning lever instead of screws, ensure that you adjust the lever so that it is TIGHT. Like so tight that you need to pull on it with paracord to loosen it and release the lever because your fingers aren’t strong enough (trust me it’s a trick). Too loose of a lever means your accessory will come loose during recoil.
• Vibra-tite or Loctite 242 are your friends. These are types of threadlocker that work great with items mounted on a firearm and undergoing recoil.
• Use the correct sized bit for the screws on your accessory. These screws and bits are often small, thus if you don’t use the correct size the screws and the bit can easily be stripped.

Rate

Click on a star to rate it!

Average rating 5 / 5. Vote count: 1

No votes so far! Be the first to rate this post.

AR-15 owners all across the nation are searching for the right hardware, AR rail systems, and accessories for them. There’s no one-size-fits-all answer because every shooter possesses a unique and distinct set of traits. Ranging from height, weight, and shooting technique to shooting frequency, shooting purpose, and aesthetic preferences, these variable factors determine what kind of accessories, receivers, and AR rail systems will be right to make your AR the total package for you.

Although we can’t tell you what is right for you, we can assure you that in a market this developed, there are options that you’re going to love once you find them. In today’s blog from the team at RailScales®, we present some high-level information about two modern and popular styles of AR rail systems — the Picatinny Rail, or Pic rail, and the more recently created M-LOK system.

Both AR rail systems are in widespread use throughout the United States, and both have some unique characteristics to offer. Our goal here is not to crown a champion or even attempt to sway you. Our goal is simply to provide some information that we hope will get you started in your search. Let’s get going.

Picatinny Rails

Of all of the modern AR rail systems — we define that as everything developed since about 1980 — Pic rails have proven they have the most staying power. In time, that may change, but as of today, Picatinny rails hold the prestigious, if unflattering, recognition as the “Old Faithful” of AR rail systems.

Developed in 1992 by a New Jersey weaponsmithing firm, Picatinny Arsenal, at the behest of the United States military. Picatinny Arsenal re-imagined the Weaver rail system that had been in use since the 1930s and combined it with some of the elements that they were using on long-range artillery — miniaturized, of course. The result was the Pic rail.

With the ability to mount hardware onto the 12 o’clock, 3 o’clock, 6 o’clock, and 9 o’clock positions on a Picatinny quad rail, not only was the US government thrilled with the result, but it allowed widespread customization for private AR owners as well.

Picatinny rails offer a consistent and wide locking slot, and a relatively sleek, angular feature. A Pic rail can accommodate a lot of hardware if you’re in the mind to load up your AR. Additionally, it is still widely considered to be the superior AR rail system for heavy-duty, advanced optics.

The M-LOK System

The M-LOK system is a real newcomer in the AR rail system marketplace. Developed in 2014, the M-LOK system was Magpul’s answer to the also relatively new KeyMod system from VLOTR Weapons Systems.

M-LOK offers some enticing benefits. First and foremost, it’s a pretty lightweight rail system, yet it still maintains a reputation — over its relatively short lifespan so far — as being more than durable enough for just about any AR user.

The M-LOK system also offers a dual point attachment platform that allows for AR 15 accessories such as lights and foregrips to be mounted with a lot of flexibility for personal preference and comfort. M-LOK systems are designed to get the most out of the least amount of material. This helps with weight, but it also helps to reduce the cost of the M-LOK AR rail system, making it a popular choice for budget-conscious shooters.

The final benefit of the M-LOK we want to cover is the system; it was Magpul’s choice to make the designs open-source, allowing designers, engineers, and arsenals everywhere to produce parts and accessories for it with the need for an adaptor.

Conclusion For These Two AR Rail Systems

Both of these AR rail systems enjoy a healthy dose of popularity and strong sales. So, which one is actually better for your needs? That all depends on what your needs are. The Picatinny rail system is more heavy-duty and built to handle heavier mounts without a loss of performance. The M-LOK system from Magpul isn’t quite as hardy, but it is lighter and has more and more tactical hardware being built for it every day.

So, if you want an AR rail system for long-range target shooting, hunting, or other shooting that requires heavy-duty, advanced optics, then the Pic rail might be a better place for you to start. However, if speed, rapid-fire accuracy, and comfort are more important to you, than chances are good you’ll prefer the M-LOK system.

The M-LOK system has positioned itself as the de facto king for this argument at this moment in time. With the ability to add Picatinny rail accessories to an M-LOK now, going the pic rail route doesn't make sense as a modern shooting enthusiast. The adaptability of the M-LOK rail system and its weight savings truly give it the edge that the Picatinny rail system just can't compete with anymore. Now if you want to be "clone correct" on some older weapon layouts, then you have to go Picatinny, those are the rules. Fortunately, for those with the more modern MLOK system on their AR-15 rails, RailScales has a multitude of products available to upgrade the function and aesthetic far beyond what a Picatinny rail could offer. 

Find M-LOK Mountable Grips, Hand Stops, and More at RailScales®

If you do decide that the M-LOK system is right for you, then visit RailScales® online today and shop our elite-quality M-LOK accessories.