Rainier Arms Precision Match Grade AR-15 Bolt Carrier Group (BCG) - Nickel Boron

NOW HP TESTED!

The Rainier Arms Precision Match Grade Nickel Boron BCG - 5.56 is machined and finished to a higher standard to meet and exceed all Mil Spec. It is machined using the most precise equipment in the industry. The bolts are MPI/HP tested & Marked to give you ultimate confidence in your weapon system.

Carrier:

Full Auto Carrier
SAE 8620
Heat Treated
Nickel Boron Plated
Bolt:

5.56/.223
Carpenter 158 Steel
Shot Peened
Heat Treated
Nickel Boron Plated
Extractor:

Machined from bar
Shot Peened
Heat Treated
Maganese Phosphate
Extractor Spring:

Chrome Silicone for Longer Life
Black Insert as per current Mil-Spec
"O" Ring is high temp resistant dark brown
Extractor Retaining Pin:

Precision Machined
Precision ground to diameter
Precision ground to length
Heat Treated
Firing Pin:

Machined and then precision ground for accuracy
Heat Treated
Gas Key Bolt:

Precision manufactured in house with extra deep knurling
Grade 8
1200 degree locking patch is factory applied to threads to help insure long lasting tightness
Gas key:

Hard Chrome lined gas tube as per Mil-Spec
Bolts installed to proper torque
Staking on both sides of both bolts
Cam Pin:

Precision machined
Heat Treated
Nickel Boron Plated
Firing Pin Retaining Pin:

Precision bent
Precision cut to length
Heat Treated
Gas Rings:

Stainless Steel per Mil-Spec
Ejector:

Precision machined
Heat Treated
Ejector Spring:

Chrome Silicone
Precision ground ends
Ejector Retaining Pin:

Precision cut to length
Hard Chrome Plated