AR15.COM Complete Bolt Carrier Group
Bolt is Carpenter 158 steel, MPI, HPT, shot peened with a tool steel
extractor and black extractor insert and tension enhancing o-ring.
Carrier is chrome lined with chrome lined, hardened gas key and Grade 8 cap screws staked per Mil-Spec.
Everything but the coating is Mil-Spec.
The DLC coating:
- Reduces coefficient friction
- Increased wear resting from foreign abrasive materials
- High pitting and corrosion resistance
- High integrity of surface structure
- Better adhesion to base materials
- Absorbs oil and retains lubricating benefits longer
- Black Finish
DLC has all the attributes of chrome, improves wear resistance and reduce
friction; thereby greatly increasing service life without the pitfalls of
chrome such as flaking and a bright finish.