Microbest Full-Auto M16 Bolt Carrier Group, Phosphate & Chrome-Lined
The Microbest Bolt Carrier Group is the measuring stick by which all others are compared.
Microbest is the OEM manufacturer and supplier of bolt carrier groups for a lot of popular rifle manufacturers, including but not limited to, Bravo Company Mfg and Sons of Liberty. Microbest is trusted to build a bolt carrier group that exceeds the MIL requirements from the right materials and processes with great attention to detail.
Assembled with Sprinco springs and inserts for longevity and reliability.
Specifications:
Bolt Assembly:
- Bolt precision machined from Carpenter 158 alloy and vibratory tumbled
- Heat-treated and shot-peened
- Individual high pressure/proof (HP) and individually magnetic particle inspection
- Extractor from 4340, heat-treated and shot-peened
- Ejector from S7 tool steel, heat-treated and shot-peened
- Manganese phosphate finish
Carrier:
- Machined from AISI 8620 steel
- Full-auto M16 profile
- Heat treated and Carburized/strain relieved
- Precision ground gas key interface
- Manganese phosphate finish with hard chrome interior
- Gas key from 4130 steel with chrome interior, secured with staked Grade 8 fasteners
Misc:
- Cam pin from 4340 chromoly steel, heat-treated
- Firing pin from 8640 steel alloy, heat-treated, hard-chrome plated
- Firing pin retaining pin from 1038 carbon steel, heat-treated
Click here to browse our entire selection of Bolt Carrier Groups & Parts.
Scott S. (verified owner) –
I am still in the process of my build, so I don’t have a review yet. I do want to comment on Rooftop’s service, it was very fast and I was really surprised to see a package of Top Ramen noodles in the package :). They made sure to inform me every step of the way on how my order was going, I really liked that.
I will be buying from them again.
JFA11 (verified owner) –
This BCG is amazing for both the price and quality. Buy two or even three of these for the price of one from anywhere. I run it on my block ii upper and works flawlessly.
Arturo Gonzalez (verified owner) –
One of the best for the money!
Jackson R (verified owner) –
Great bcg and quick shipping. Thank you!
Daniel Bedwell (verified owner) –
Can’t beat one of the best mfg. had it quickly.