Walker Defense Dark Matter

High-Polish DLC BCG Review

The heart of an AR15 is the Bolt Carrier Group or BCG. A quality BCG can make your rifle perform like a champion. A mil-spec BCG might work, but will not perform as well, especially if you are trying to get the best performance out of it. Walker Defense Research has released their Dark Matter Bolt Carrier Group. This highly polished, fitted, and DLC coated BCG is of the utmost quality.

When looking for a Bolt Carrier Group, either to replace one or for a new build, there are things to consider. Do you want cheap, or are you looking for top quality that will last forever? The Walker Defense Dark Matter BCG is in the top quality group. To start with, it is a M16 style full auto carrier. So if you are fortunate to have a full auto M16, M4, etc, it will work with that. More important is the fact that the M16 carrier has the full mass, which allows it to run more smoothly, at least in my opinion. This Dark Matter carrier is also made from 8620 tool steel for a lifetime of use.

The Dark Matter BCG has a bunch of hi-end specifications. Some of these I will describe more in depth later. This BCG is for standard calibers and for use in direct impingement guns. These include 5.56/.223/300 blk, etc. It weighs 11-⅝ ounces and is made to true mil-spec dimensions. On the front end it has a C158 bolt that is magnetic particle inspected and high pressure tested. The 4130 gas key is properly staked using Optimized Carrier Key Screws (OCKS). These screws are deeply knurled to allow the staking to dig in, making them almost impossible to come loose. Lastly, the Dark matter BCG is DLC coated.

Walker Defense is all about small batch quality. Here is what they have to say about the Dark Matter BCG: “We’ve always leaned into our advantage as a company specializing in small-batch production, but we’re taking it further. Those extra touches of quality add up and give us the ability to do things that larger companies just can’t. A few quick tangible examples of this:

Each carrier is matched by hand to each bolt and cam pin to prevent tolerance stacking and to ensure ideal, consistent fitment as the bolt cams back and forth.

We also pair each bolt with its firing pin to confirm adequate protrusion for reliable primer ignition.

Using OCKS screws for ultra-aggressive staking of the gas key, so it won’t loosen at high round counts”

Those are just a few things Walker Defense does to give you the best BCG around.

DLC, or Diamond-Like Carbon coatings have been around for a while, but the Dark Matter BCG takes it to a new level. DLC coatings by themselves are extremely hard, corrosion and wear-resistant, and very slick, which gives them low coefficients of friction and superior dry lubricity. Walker Defense takes this up a notch by aggressively polishing the bare metal, before it is coated. As with most machined parts, a BCG is only as good as its base metal. This polishing is a very labor intensive process which makes the Dark Matter BCG super slick and mirror-like shiny. Then after a high quality dark black DLC coating is applied, they polish the DLC coated BCG again. This makes the BCG even more slick (and also hard to take pictures of because of the mirror finish it produces). By polishing the BCG before and after coating, you get an extremely smooth surface that carbon has a hard time sticking to. Cleanup on the Dark matter BCG is super easy. One can literally just wipe it off with a rag. Carbon just doesn’t stick to this BCG.

I am using the Dark Matter BCG in a 300 blackout AR pistol. This pistol ran suppressed for around 60% of the review. Why does this matter? Because the pistol gets a lot dirtier. The upper on this pistol is nothing special, just your off the shelf AR upper receiver. Before installing the Dark Matter BCG, I was running a Mil-Spec BCG. After I installed the Dark Matter BCG I could tell a smoothness difference. Not just in how the gun cycles under use, but also when hand cycling the action. The AR pistol is just way more pleasant to shoot now. Another thing I noticed was that the brass ejection was more consistent than with the mil-spec BCG. I attribute this to the action cycling smoother. After around 800 rounds, I can’t even really notice any wear on the Dark Matter BCG, a testament to that fantastic polished DLC coating.

The Walker Defense Dark Matter BCG is slick, pun intended. This BCG is of the utmost quality. It has all the standard features you would want in a high quality BCG: MPI and HPT tested, DLC coated, quality base metals, and true mil-spec dimensions. That does not even count the “extras” Walker Defense puts into these. One would be hard pressed to find a better, or smoother BCG. The price on these is very reasonable for what you get, definitely a high value to price ratio. If you are looking for the slickest, highest quality BCG around, definitely go look at the Dark Matter High Polished BCG from Walker Defense. These are literally super slick.

Firearms Insider Reviews - Key Points

Claim to Fame:

Super slick, high quality bolt carrier group that is easy to clean

Target Market:

Those wanting a superior BCG

Features, Benefits, and Specifications of this product:

Coating: Highly-Polished DLC
Compatibility: M16/ M4 / AR-15 Using Direct Gas Impingement (not for use in piston guns)
Calibers: 5.56x45mm NATO / .223 Remington / .300 AAC Blackout
Profile: Full Auto Style Carrier w/ Properly Staked Gas Key
Bolt: C158
Carrier: 8620 Tool Steel
Total Weight: 11 5/8 OZ.
True Mil-Spec dimensions
4130 steel gas key
Staked with OCKS Screws
4140 steel extractor and cam pin
Hard chrome ground 8740 steel firing pin
Magnetic particle inspected
High Pressure Tested (HPT)
Made in the USA