BA10 Assembled Upper Receiver. Forged from 7075-T6 aluminum, this assembled upper is precision machined to DPMS Gen1 specifications and features M4 feedramps. The BA10 Assembled Upper Receiver comes with both the port door and forward assist hardware preinstalled. Forged from 7075-T6 aluminum, this assembled upper is precision machined to accept standard .308 components and is the perfect upper for your big bore build. Match this with our BA10 lower receiver for a solid and dependable fit.