At some point, you will have encountered someone using handguards on modern AR-15s. Some of them may even be using something to cover the rails on their gun. This might seem a little redundant, but it raises the question “Should you use rail covers on your rifle?”
We are going to go over some of the reasons you might want to adopt rail covers and what we prefer to cover our rails with. But first, we need to address some of the major handguard/rail options on the market.
Handguard Types
For modern-style AR-15s there are essentially three major handguard types that are compatible with rail covers, they are Picatinny, M-LOK, and KeyMod.
Picatinny
Picatinny was one of the major rail systems in the early 2000s. Commonly called “quad rails”, Picatinny rails were a great solution for the need to mount lights and lasers on the handguard of the rifle. The rail was so popular, that modern rail systems will still sometimes use one or more “strips” of Picatinny on the top of their handguards for 12 o’clock mounting options
M-LOK and Variants
After Picatinny’s initial success, there was a need to create a lighter option with more versatility. Magpul would develop the M-LOK mounting system during their Masada/ACR rifle project and eventually would license out the design to other manufacturers free of charge after an approval process.
This style of rail would eventually become the de facto industry standard for AR-15s and be implemented on pretty much every handguard design after 2015.
KeyMod
While it does predate M-LOK, KeyMod was released two years before by VLTOR Weapon Systems to make a more universal mounting platform. It allows for direct mounting of accessories but was not as repeatable as M-LOK.
KeyMod was an open source design to encourage its adoption across the industry but it didn’t catch on like M-LOK did. You can still find KeyMod handguards, but the availability of compatible rail covers and other accessories will not be as broad as M-LOK or Picatinny.
Reasons to Use Rail Covers
Rail covers are a matter of preference but there are some solid benefits from using them. These are comfort, heat mitigation, ergonomics, and convenience.
Comfort
While some may not consider comfort to be high on their list when it comes to their rifle, if you are not comfortable with your rifle it will impact your performance. This is especially true if you prefer to shoot without gloves.
Rail covers provide a comfortable area to rest your hand while you are shooting. This is especially handy for the “cheese grater” Picatinny quad rails. Handguards are still metallic and metal can get some shart/hard edges that are no fun to scrap your hand across.
Heat mitigation
Depending on your environment and the amount of shooting you do, heat is a big factor with your rifle. Every shot put heat into the barrel and eventually the handguard. The more heat you produce, the hotter the barrel and handguard will get.
Could you wear a glove to mitigate this? Yes, but after a while the heat can become unbearable. Rail covers, especially those made from G10 or aluminum can make that heat less noticeable for longer. This is because they act like heat sinks, storing up the excess heat energy until they are allowed to rest.
Ergonomics/Control
Rail covers can improve the ergonomics of your rifle and can help promote control. Once you have figured out your proper grip placement, a rail cover can be placed there to give a physical reminder of where your hand should go.
These rail covers can be textured to provide a more comfortable grip while providing better traction. This makes it easier to hold onto the gun and control it rather than slipping and sliding with a smooth aluminum handguard.
Dead Space Control
While M-LOK has a lot of attachment points it also has a lot of dead space. Open air and rail sections make mounting accessories easy but increase the snag points your hand may encounter.
Jamming a finger or catching a finger on a rail, especially an aluminum rail, can cause enough injury to throw off your match. This is especially true if you are going as fast as you can on the clock.
Having a rail cover keeps your fingers where they should be without having to swap out your handguard so you can focus on the stage or whatever you’re doing instead of worrying about where your hand is.
Our Preferences
When it comes to selecting any accessories for your rifle, your situation and preferences will be the deciding factor. But since people do like suggests we’ll go over what we prefer to use at Guntology.
Our choice for handguards is the Forward Controls (FC) MCH-A. These handguards are the aluminum version of their G10 rail covers. The original G10 design was very usable and was our go-to rail cover for a long time.
However, these new aluminum options bring more to the table. The MCH-A has FC’s all-angle dimpling which provides a comfortable gripping surface from pretty much every direction. There are no sharp edges on the panels courtesy of FC’s quality control and attention to detail.
Each MCH-A panel features three lines of dimpling, with the centerline of dimples having a hole that goes through the panel. This hole was originally designed to allow for drainage and still works in that capacity. The interesting aspect of this hole is that it also allows for better heat dissipation.
Since the panel is made out of aluminum it does heat up just as fast, if not faster, than the original G10. However, since it is metal and it does have those air holes, the MCH-A cools faster than the G10 panels. This makes the whole panel act like a radiator bringing the advantage of being ready to use a few minutes sooner than the G10.
The G10 panels were great insulators but they retained the heat for longer. When we were conducting our stress tests, the aluminum panels would heat up to anywhere from 50 to 80 degrees hotter than their G10 counterpart. But the G10 would consistently be 20 to 30 degrees hotter than the aluminum panel after cooling for a 5 to 15-minute interval.
The cooling benefits of the MCH-A and overall durability/quality of the Forward Controls’ products are enough for us to switch over to this style of rail cover. If you want to spend more time shooting, you need to have your gun cool faster when you aren’t using it.
Now you won’t be putting as much stress on your rifle as we did for our test (the rail of our test rifle was 530 F°), but keeping the gun holdable is nice when you live in a hot climate and have to shoot for extended periods.
