The KAK M16 Bolt Carrier Group (BCG) for 5.56 NATO and .223 Remington is a premium-duty component built for shooters who demand maximum reliability, durability, and proven mil-spec performance. Featuring a chrome-lined phosphate carrier and a Carpenter 158 (C158) steel bolt, this BCG combines battle-tested materials with precision manufacturing to deliver dependable operation in defensive, duty, competition, and recreational AR-15 platforms.

At the heart of this bolt carrier group is a Carpenter 158 bolt, the military specification steel trusted for decades in hard-use rifles. The bolt is machined from a single piece of C158 steel, properly heat treated, shot peened, precision ground, and MPI (Magnetic Particle Inspected) to ensure long-term strength and reliability under demanding firing schedules.

The full-auto M16 carrier is machined from aircraft-grade 8620 steel, heat treated, chrome lined, and phosphate finished to provide exceptional resistance to wear, corrosion, and carbon buildup. The chrome-lined interior promotes smoother operation and easier maintenance, while the phosphate exterior provides a durable protective finish trusted by military and law enforcement users worldwide.

Additional enhancements include a one-piece billet extractor for improved extraction reliability, a chrome-plated firing pin, S7 tool steel ejector components, and a chrome-lined 4130 gas key that is hydraulically staked and sealed with Permatex gasket sealant to ensure proper gas system integrity.

Whether you're assembling a duty-grade AR-15, upgrading a defensive rifle, or building a reliable range gun, the KAK C158 Chrome-Lined Phosphate BCG delivers the durability and performance serious shooters expect.

Features:

• Compatible with 5.56 NATO and .223 Remington
• Full-auto M16 carrier profile
• Carpenter 158 (C158) steel bolt
• Aircraft-grade 8620 steel carrier
• Chrome-lined carrier interior
• Chrome-lined gas key
• Durable phosphate finish
• Shot peened bolt
• MPI-tested bolt
• One-piece billet enhanced extractor
• Chrome-plated firing pin
• S7 tool steel ejector and extractor retaining pin
• Hydraulically staked gas key
• Permatex gas key sealant for enhanced sealing

Benefits of a C158 Bolt:
Carpenter 158 steel remains the benchmark for military-spec AR-15 bolts due to its proven toughness, durability, and ability to withstand high round counts and harsh operating conditions. Combined with proper heat treatment, shot peening, and MPI testing, this bolt is built for long-term reliability.

Perfect For:

• AR-15 rifle builds
• Duty and defensive carbines
• Law enforcement rifles
• Training and range rifles
• Hard-use applications
• Mil-spec rifle upgrades