Microbest Full-Auto M16 Bolt Carrier Group, Chrome & Phosphate Extractor
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, manganese phosphate finish
- Ejector from S7 tool steel, heat-treated and shot-peened
- Hard chrome-plated finish
Carrier:
- Machined from AISI 8620 steel
- Full-auto M16 profile
- Heat treated and Carburized/strain relieved
- Precision ground gas key interface
- Gas key from 4130 steel, secured with staked Grade 8 fasteners
- Hard chrome-plated finish
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.
Ethan (verified owner) –
I love those Microbest, I personally run them in all my builds. They clean up really easily. Usually a microfiber will take off most the carbon. I haven’t had a single failure yet with thousands of rounds. Highly recommend
John (verified owner) –
I just bought one excellent service and shipping I don’t know why people buy more expensive bcg’s when this one is the best I don’t know anyone that’s had problems with microbest
Anthony R. (verified owner) –
Bought 3, all have “clean” machining. Study the specs!!! CAN’T beat @this price point! Compared to a recently purchased “sandcutter” carrier only, Microbest has the superior machined finish. Shout out to Rooftop for their impeccable customer service. Thanks for providing us quality choices at great prices.
Ryan (verified owner) –
The best BCG I think I’ve ever put hands on. Easily outclasses anything else in it’s price range.
Cody (verified owner) –
Shoot good. Monkey like. Bought 2.