Mil-spec AR bolt carrier groups, forged and coated for reliability.
A quality bolt carrier group drives the reliability in your upper receiver, literally: It's responsible for chambering and ejecting rounds, and managing your direct-impingement gas system to ensure your AR cycles reliably. We've worked carefully to source quality, mil-spec, Full Auto-profile BCGs that are made to interface with the most popular AR calibers and platforms!
Our relatively small selection of bolt carriers is purposeful: You only need one solid bolt for your caliber with the best specs. Each of our available bolts is configured with the following:
Sporting incredibly high tensile and yield strengths, these bolt carrier groups are capable of handling high-pressure rounds like 6.5 Creedmoor and 6.5 Grendel, while affording superior heat and wear resistance during rapid fire. They're properly hardened and coated to ensure they remain resistant to corrosion and fouling for years to come and tens of thousands of rounds down the tube.
Read our Full Guide to the AR-15 Bolt Carrier Group
With so many calibers and uppers available, it can be tough picking out the right components for your AR-type rifle or pistol. Rest assured the bolt carrier groups available here are made to work with all the popular calibers currently available:
The available 9mm AR parts we list are designed to work with the popular (but proprietary) PSA-designed G9 Hybrid BCG. This bolt carrier group is designed to operate with blowback functionality, ditching the traditional direct-impingement or piston-driven AR gas system. These bolts are included with our available AR-9 parts and 9mm upper assemblies.
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