AR15 Assembly & Function Service OSA AR-15 Assembly & Function Service Building an AR-15 has never been easier—but building one that is reliable, accurate, and properly tuned takes experience. At OSA, we don't simply install parts and hand the rifle back. Every build is... MSRP: Was: Now: $0.00 Choose Options
Gas Block Pinning Service OSA Gas Block Pinning Service A properly installed gas block is the foundation of a reliable AR-15. While quality set screws and proper installation are sufficient for many rifles, cross-pinning the gas block provides the highest level of mechanical... MSRP: Was: Now: $50.00 Add to Cart
Pin & Weld Muzzle Device Service OSA Pin & Weld Muzzle Device Service Need to make your 13.7", 13.9", or 14.5" AR-15 barrel compliant with the federal 16" minimum rifle barrel length? Our Pin & Weld Service permanently attaches your muzzle device to the barrel using ATF-accepted... MSRP: Was: Now: $75.00 Add to Cart
