BCA’s stripped flat top upper receiver is a perfect start for your AR build, from a standard 5.56 NATO M4 style rifle to a 300 Blackout hunting upper. This upper receiver is the perfect foundation for any AR-15. Made from 7075 aircraft aluminum to milspec, these anodized billet uppers will stand up to the abuse these rifles are known to take. This upper does not include forward assist and dust cover.
What magazine/ammo does BCA recommend for each caliber?
These are brands that BCA uses in the facility to test fire our products. However, there are several brands that will also function properly. Caliber Magazine Ammo Grain Weight Ammo Brands BCA Status AR15 - 223/5...