The bolt carrier group (BCG) does the work every time you pull the trigger. Do not cheap out here.
What to look for
- Full-auto (M16) profile: a bit heavier and smoother. Fine for semi-auto rifles
- Staked gas key: keeps the screws from backing out
- Shot peened, MPI and HPT tested bolt: checked for cracks
- Finish: phosphate, nitride or nickel boron
Price runs about $120–250. See Bolt Assembly for the parts inside.
Watch
Shop AR15 gear
- AR15 parts at OpticsPlanet
- AR15 upper parts at OpticsPlanet
- AR15 lower parts at OpticsPlanet
- AR15 triggers at OpticsPlanet
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