16" M4 5.56 Carbine Barrel + Complete Nitride BCG

16" M4 AR-15 5.56 .223 Carbine Barrel + Complete Nitride Bolt Carrier Group

Barrel Info:

This 5.56 chambered 16" M4 Profile Barrel is machined from 4150 Chrome Moly Vanadium steel with a QPQ Corrosion Resistant Finish and QPQ coated M4 feed ramp extension.

Quench Polish Quench (QPQ) is a specialized type of nitrocarburizing case hardening that increases corrosion resistance. It is sometimes known by the brand name of Tufftride, Tenifer Black Nitride or Melonite. QPQ is a huge improvement over Chrome Lined barrels. Unlike chrome lining, where the chrome is built up on the surface, QPQ converts the surface without the risk of dimensional build up. 

The best BCGs for replacement parts and builds have strong and dependable carriers with trusty bolt assemblies that cycle reliably. That's exactly what you'll get with this high quality complete BCG. Prime Manf M16 bolt carrier groups undergo black nitride process, producing a beautiful finish and reducing the friction coefficent. The carrier is made from 8620 steel. The bolt is made from 9310 Vac-Arc Premium Carburizing Steel which has a high core hardness and high fatigue strength unlike standard Hot/cold rolled 9310 steels. The 223 Bolt and Bolt Carrier Assembly is compatible with 5.56 NATO and 300 Blackout.

• 9310 Vac-Arc Premium Carburizing Steel (Bolt)
• 8620 Tool Steel (Carrier)
• Mil-Spec Extractor Spring, black extractor insert, Viton O-Ring
• Tool Steel Extractor
• Shrouded Firing Pin
• Mil-Spec Gas Key (4140 Steel) attached with Grade 8 hardware and heavily staked
• Caliber: .223 / 5.56 / 300 Blackout
• Bolt is shot Peened and MPI
• Carrier has flats or is "Facetted"