Browse AR-10 upper build assemblies if you are moving up from the AR-15 platform to a full-power rifle round. Every upper in this category is chambered in .308 Winchester and ships complete, with the bolt carrier group and charging handle installed, so it is ready to mount on an AR-10 lower receiver. Choose a 16″, 18″, or 20″ barrel, a 12″ or 15″ free-float handguard, and a finish to match the rest of your build. To compare options by barrel length, rail style, and color, go to our .308 upper build assemblies.