Bushmaster Post-Ban DCM-XR Competition Upper Receiver/Barrel Assembly
M16A2 Dual Aperture “Stay-Straight” Rear Sight is specifically modified to accept interchangeable apertures available in four sizes to suit the competitor’s vision and preference… .040" (Standard); diameter. Additionally, the dual detent rear sight with Competition Hood is configured for 1/4" Minute of Adjustment for both Windage Knob and Elevation Drum. Rear sight cover included.
Competition Front Sight is specially ground on three sides for optimum clarity, and is .052". It is secured within the front sight base by a set screw to avoid the possibility of any movement once the rifle has been “zeroed”.
20" Extra Heavy Competition Barrel is a full 1" diameter under the free float tube, and is precision button rifled 1 turn in 8" – right hand twist – 6 lands and grooves. The Barrel material is ChromeMoly Vanadium Steel, and the Firing Chamber is machined to SAAMI specifications. It is lead lapped and hardened to Rockwell C26 to 32. This barrel is not Chrome lined and includes an A2 flash hider. In the Upper Receiver, the Bolt is carefully matched to the Barrel Extension Lugs for precise lockup, maximum strength and optimum accuracy.
The handguard set looks like government issue parts, but is actually a Competition “Free Floater” Tube (handguard tube/barrel nut combination). It does not contact the Barrel forward of the Receiver. A sling swivel is attached to the forward end of the tube to avoid any possibility of deflection or pressure on the barrel that could degrade accuracy.
Part No: PURA2B 20CG8. Retail Price: $790.00
Approx. 200 rounds down the barrel. This upper is in mint condition, no scratches-dings or wear. My kid has other interests and just doesn’t want to shoot. 
First $650 takes it - shipping and ins. to lower 48 included. USPS money order only.