Patent Pending

The KAK AR-15 5.56mm K-SPEC Down Vent Bolt Carrier Group (BCG) combines multiple key features focused on increasing the reliability of your AR15 style firearm no matter if you are running suppressed or unsuppressed , and regardless of conditions.  The K-SPEC is a truly plug and play BCG that will accommodate whatever configuration your mission requires.

For those running suppressed, the K-SPEC requires no additional tuning or tweaking of the gas or recoil systems to run reliably. Like all KAK BCGs, the K-SPEC is machined to the M16 full auto profile.

Reduced Peak DB Report

When used in conjunction with a silencer, the gas redirect produces a quieter report

See testing results here- Down Vent vs Side Vent DB reduction testing

Slotted Angled Carrier Rails

For enhanced functionality in adverse and rugged conditions such as sand, mud, dirt, and grime. These rail cuts are designed for debris disbursement, resulting in ultra-high functionality in the toughest conditions, including suppressor fouling and foreign contaminates. Strategically located angle cuts in the rails result in fouling and debris being moved into noncritical areas that are not in contact with the upper receiver and do not affect the function of the firearm, aka sandcutter.

Downward Gas Vents

In an effort to reduce the amount of debris and gas vented towards the shooters face, the two standard gas relief ports have been relocated from the ejection port side of the K-SPEC carrier and placed underneath, in the magazine feed lip channels. Two additional emergency relief ports have also been added to the bottom of the carrier to mitigate structural damage in the event of a case head separation.  Testing has shown that venting the gasses through the magazine well has no negative impact on the feeding or function of the magazine nor ammunition, and any added heat is negligible.

Dual ejectors

The K-SPEC dual ejector system uses mil-spec ejectors and springs that require no proprietary parts. Ejector holes are centered on the lugs to avoid any reduction in strength of the bolt. The dual ejector system increases the ejection reliability and adds consistency to the ejection pattern. KAK Industry has been manufacturing dual ejector bolts for the AR10/LR308 platform for over a decade and has used that experience to create a durable and reliable dual ejector system for the AR-15 platform.

• Designed to function reliably in the toughest conditions
• Optimized for both Suppressed and Un-suppressed use, All uses – All Conditions
• Dual Ejectors for enhanced reliability
• Angled Carrier Rail Cuts for flawless function in adverse conditions and prolonged suppressed use
• Downward Gas Ports to reduce gas blowback to shooter
• Full Auto Profile
• Permatex added between Gas Key and Carrier Mating Surface
• Carrier- 8620 steel, outside rails, bolt runs, and gas bores ground to .0002 tolerances, NP3 Finish, Chrome Lined
• Bolt- 9310 steel, outside diameters ground to .0002 tolerances, MPI test, NP3 finish
• Firing Pin- 8740 steel, Swiss turned, heat treated, precision ground, chrome plated
• Cam Pin – 4140 steel, Swiss turned, heat treated, NP3 finish
• Extractor- 4140 steel, fully machined, Phosphate coated
• Extractor pin- S7 tool steel, ground, heat treated
• Ejector- S7 tool steel, ground, heat treated
• Gas key – 4130 steel, heat treated, NP3 finish, secured with T25 torx fasteners, torqued to spec, staked with  hydraulic staking machine
• 11.5 oz

Machined in house and assembled using only the finest steels and AR-15 parts. 

KAK Industry takes pride in producing some of the finest Mil-Spec/ Enhanced AR-15 bolt carrier groups available, made 100% in house at our MO facility using Doosan machining centers, Tsugami Swiss turning, and the latest in FANUC robotics combined into an automated cell giving us lights out production capability. In-house automated CMM Inspection processes ensure consistent quality.

NP3 coating is a specialized type of coating often used in firearms and other high-wear applications to enhance durability and reduce friction. It’s known for its ability to offer excellent resistance to wear, corrosion, and fouling. The NP3 coating is a proprietary finish.

The coating is applied through an electroless nickel plating process combined with a fluoropolymer, which gives it its unique properties. The fluoropolymer component helps to reduce friction, which can improve the performance and longevity of the coated parts. This makes NP3 particularly popular for use in firearms, where its low friction and resistance to corrosion and fouling are highly valued.