This full build kit combines an 11.5 inch KAK Industry .223 Wylde barrel with a carbine gas system and 1:8 twist, delivering chamber flexibility for both .223 Remington and 5.56 NATO ammunition. The government profile barrel is nitride treated 4140 CrMoV steel, providing surface hardness and heat resistance that extend barrel life under sustained use. The upper receiver is machined from 7075 T6 aluminum with M4 feed ramps and an anodized finish, paired with a 10 inch ACE-20 Series M-LOK freefloat handguard constructed from 6061 T6 aluminum. The kit includes a complete bolt carrier group with a 9310 alloy steel bolt, nitride finished charging handle, and a micro low-profile gas block sized at 0.750 inches. The SB Tactical SBA3 adjustable pistol stabilizing brace offers five length of pull positions, and the GI A2 birdcage flash hider threads onto the 1/2x28 muzzle.
Key Features
Perfect For
The .223 Wylde chamber specification allows you to run both .223 Remington and 5.56 NATO cartridges without the pressure concerns that come from firing 5.56 in a dedicated .223 chamber. The 1:8 twist rate stabilizes bullet weights from 55 to 77 grains, making this barrel practical for everything from bulk training loads to heavier precision ammunition. The carbine gas system in an 11.5 inch barrel delivers reliable cycling without excessive port pressure, and the nitride treatment on the 4140 CrMoV steel creates a hard, slick surface that resists carbon fouling and throat erosion. The government profile maintains material at the muzzle end for durability while reducing weight near the chamber.
The 7075 T6 aluminum upper receiver provides the material strength needed for bolt lockup and pressure containment, with M4 feed ramps machined into the receiver extension for improved feeding reliability with a wide range of ammunition profiles. The anodized finish offers corrosion resistance and a consistent black appearance. The 10 inch ACE-20 Series M-LOK handguard is constructed from 6061 T6 aluminum, keeping weight down while providing M-LOK slots along the handguard length for modular attachment of lights, grips, or other accessories. The freefloat design eliminates handguard contact with the barrel, preserving accuracy potential by preventing pressure on the barrel during shooting.
The included bolt carrier group uses a 9310 alloy steel bolt, a material choice that delivers superior strength and fatigue resistance compared to standard Carpenter 158 steel. The nitride finish on the carrier group adds surface hardness and lubricity, reducing friction during cycling and extending service life between cleanings. The mil-spec charging handle provides a reliable grip surface for charging and malfunction clearance. The micro low-profile gas block meters gas flow with a 0.750 inch diameter fit, tucking cleanly under the handguard without adding bulk or snag points.
The SB Tactical SBA3 adjustable pistol stabilizing brace is one of the most widely used braces in the AR pistol market, offering five positions of length of pull adjustment to accommodate different shooting positions and arm lengths. The brace uses a minimalist design with an integrated QD socket and adjustable nylon strap. The GI A2 birdcage flash hider is a proven design that disrupts muzzle flash signature, reducing visible flash during low-light shooting. The 1/2x28 thread pitch is the industry standard for .223 and 5.56 muzzle devices, allowing you to swap to a different brake, compensator, or suppressor mount as needed.
Follow safe handling and manufacturer instructions
Ensure compliance with all applicable laws
Verify component compatibility before use
Inspect all components prior to use
Barrel: KAK Industry 11.5" .223 Wylde Carbine Gas Government Profile Barrel, 1:8 Twist
Caliber: .223 Wylde
Barrel Length: 11.5-inch
Barrel Material: 4140 CrMoV
Barrel Finish: Nitride
Barrel Profile: Government
Barrel Twist Rate: 1:8
Barrel Thread Pitch: 1/2x28
Barrel Gas System Length: Carbine
Handguard: ACE-20 SERIES 10" MLOK FREEFLOAT HANDGUARD
Handguard Length: 10-inch
Handguard Material: 6061-T6 Aluminum
Handguard Color: Black
Handguard Style: M-Lok
Upper Receiver: AR-15 Upper Receiver, M4 Feed ramps
Upper Receiver Material: 7075 T6 Aluminum
Upper Receiver Finish: Anodized
Gas Block: Micro Low-Profile Gas Block, .750 O.D Barrel Steel
Gas Block Size: 0.750
Muzzle Device: AR-15 1/2x28 TPI GI Birdcage Flash Hider 5.56 .223 A2
Muzzle Device Thread Pitch: 1/2x28
Charging Handle: AR-15 M4 Charging Handle Mil-Spec Quality
Bolt Carrier: AR-15 5.56/.223/.300/.350 Complete Bolt Carrier Group
Bolt Carrier Material: 9310 Alloy Steel
Bolt Carrier Finish: Nitride
Pistol Brace Information: SB Tactical SBA3 Adjustable Pistol Stabilizing Brace
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