

Two of CMMG’s most popular black rifles are getting a heck of a lot less, well, black. The Missouri manufacturer recently announced it is now offering the Mk4 RCE and Mk3 CBR in a Flat Dark Earth finish.
The move follows a bit of an emerging trend in AR-style rifles, with more and more manufacturers offering different finishes to existing models. And CMMG’s move to FDE on two of its carbines does have some practical potential.
Depending on the area of operation, the finish could help a shooter blend into their surroundings better. This could be a particular perk for individuals, such as western coyote hunters. But, as one of CMMG’s co-owner's points out, the new finish also continues the ethos of the AR being a rifle that can be tailored to any situation or liking.
“Flat Dark Earth finish gives our rifles a new look and allows customers to further customize the rifle to their liking,” Jeff Overstreet said. “For us, it's a great opportunity to provide something different and further enhance our rifle line-up.”
The Mk4 RCE in FDE is available in 5.56x45mm NATO or .300 Blackout and the Mk3 CBR is chambered in .308 Winchester.
Both are outfitted with 16.1-inch medium taper barrels. In both cases, the barrel has a salt-bath nitride finish (black), which is corrosion resistant. They are also outfitted with SV muzzle breaks, which should aid in reducing recoil.
The Mk4 and Mk3 each boast Geisseler SSA 2-stage triggers, which should provide a much cleaner, less gritty trigger pull over standard MIL-SPEC. Both rifles also feature Magpul MOE Pistol Grips.
The Mk4 and Mk3 both have KeyMod handguards, made from milled 6061 T6 aluminum. And each rifle features a full-length Picatinny rail along its 12 o’clock. Both rifles are also outfitted with Magpul adjustable stocks.
The Mk4 ships with a 30-round PMAG, while the MK3 comes with a 20-round PMAG. The Mk4 has an MSRP of $1,499 and the Mk3 a price of $2,149.
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