The Daniel Defense MK12 is the maker’s take on the special purpose rifle, finished in black and chambered in 5.56 NATO (Daniel Defense part no. 02-142-13175-047). It is built around an 18-inch stainless steel barrel whose chamber is formed during cold hammer forging, then DLC finished for wear resistance. A rifle-length direct impingement gas system and a MK12 gas block, built to Crane specifications for USSOCOM, drive the action. A free-floating 12-inch picatinny quad rail carries optics and accessories, and a Geissele SSA two-stage trigger sharpens the shot. It is a precision-minded AR-15 for range work and designated-marksman style builds.

Key Specifications

• Caliber is 5.56mm NATO, widely available and well suited to match-grade loads.
• The barrel is 18 inches of cold hammer forged, DLC-finished stainless steel in the MK12 profile, a heavy contour that keeps groups tight.
• Twist rate is 1:7, matched to heavier 5.56 bullet weights.
• The gas system is rifle-length direct impingement with a MK12 low profile gas block of hardened 416 stainless steel.
• The handguard is a 12-inch free-floating picatinny rail, which leaves the barrel unloaded and offers mounting space all around.
• The trigger is a Geissele SSA two-stage, giving a clean, predictable break for precision shooting.
• The GRIP-N-RIP charging handle is independently ambidextrous, so left- and right-handed shooters can work it.
• The muzzle has a Daniel Defense flash suppressor on a 1/2×28 thread, so other muzzle devices can be fitted.
• It ships with one DD Magazine and a hard case, and sights are sold separately.
• It weighs 7.41 pounds and measures 34-3/4 to 37-7/8 inches overall with the muzzle device.

Frequently Asked Questions

What trigger does the MK12 use? It is fitted with a Geissele SSA two-stage trigger, chosen for a precise, consistent pull.

Does it include sights? No. Sights are sold separately, and the long picatinny rail gives plenty of room for an optic and iron sights.

What is special about the barrel? It is 18-inch stainless steel with a chamber created during cold hammer forging and a DLC finish, which the maker says gives precise chamber-to-bore alignment and durability.

Buy the Daniel Defense MK12 5.56 NATO Rifle, 18-Inch Stainless DLC Barrel, Black

If you want a classic special-purpose AR-15 layout with a stainless DLC barrel and a two-stage trigger, the MK12 delivers it. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL, and see more of the Daniel Defense lineup in our AR rifles category.