18” Fulcrum 6.8 SPC Upper Assembly with Tube/Modular ForearmBase Components: The base upper includes the following components, all of which we will assemble for you before shipping: upper receiver with port door and forward assist, bare stainless barrel, low profile gas block, gas tube, forearm and Stag 6.8 bolt. If you want something ready to shoot right out of the box (assuming you have a lower assembly ready to go), you will need to add a bolt carrier, charging handle, and muzzle device.
Bolt Options: This upper assembly comes standard with a Stag 6.8 SPC bolt (black phosphate). If you select a different bolt from the “Bolt Options”, your build will be upgraded accordingly. We check every bolt / barrel for proper headspace before they leave our shop. For more information on the bolts we stock, click HERE.
Bolt Carrier Options: If you choose to purchase a bolt carrier along with your upper, it will be assembled for you and include the gas key and firing, retaining and cam pins. For more information on the bolt carriers we stock, click HERE.
Barrel Info: This 6.8 upper is built around one of our Fulcrum profile 416 stainless steel barrels, which features the 6.8 Bison chamber, 4-groove / 1:10” twist button rifling, a 5/8-24 thread muzzle, mid length gas system and M4 feed ramps. Each barrel is hand fitted to the upper receiver during assembly to ensure smooth cycling. For more information on Bison Armory AR-15 barrels, click HERE.
Forearm Info: We currently offer Yankee Hill and White Oak basic free float forearms, Aero Precision Quantum forearms, and JP Modular forearms. These forearms do not have integral picatinny rails, and some have limited (or no) attachment points for accessories such as sling-swivels and bi-pods while others have several attachment points. For more information on the AR-15 free float forearms we stock, click HERE.
Additional information about most of the components we use in our builds is available through our “Product Information” page HERE.
If you are unfamiliar with AR-15 barrel maintenance and new barrel break-in, we encourage you to view our "Maintenance" page HERE for some tips on getting the most out of your firearm.
Shipping: Upper Assemblies based on in stock barrels usually ship 10-15 business days from the date of purchase. We ship via UPS to addresses within the contiguous United States, and USPS Priority to Alaska and Hawaii.
Billing: Your credit card is charged for the full amount of your purchase at the time you place your order, not when your order ships.