AR10 style bolt carrier groups deal with a lot of abuse from the corrosive 308/7.62 cartridges. Using premium parts ensures that your rifle stays reliable and smooth. We only stock parts for the DPMS pattern large frame rifles. If you need Armalite pattern parts, call us and we can special order. Brands like LMT, and JP Enterprises will make sure you're never down in the fight, while some remain cross compatible with both platforms.