The 5.56 PDW Base 7.5" Upper is a short barreled pistol piston upper that incorporates the patented Adams Arms technology and the Samson Evolution extended free floating forearm. It comes with our proprietary Melonited heavy contour barrel and pistol length gas piston system. Because the piston chamber is the same size as the chamber on the rest of the Adams Arms gas lengths this 7.5" upper now has the proper dwell time to get cyclic rate and bullet velocity needed to make this a viable short barreled option for any CQB scenarios. We've also added a 4" Samson drop in rail for any shooters tactical options. This creates the shortest, most reliable, and accurate complete upper.
Upper Receiver: A4 Flat-Top, Forged
Barrel Length: 7.5"
Barrel Contour: Government
Barrel Material: 4150 Chrome Moly Vanadium Steel
Muzzle Thread Pattern: 1/2"-28
Chrome Lined: No
Barrel Finish: QPQ Melonite / Black Nitride
Twist Rate: 1 in 7"
Chamber: 5.56x45mm NATO
M4 Feed Ramps: Yes
Bolt Carrier: 1-Piece w/Integral Piston Strike Face
Muzzle Device: A2 Flash Hider
Gas System Length: Pistol, Short Stroke Piston Operated
Gas Block Diameter: 0.750"
Handguard: 2-Piece Drop in Quad Rail
Sights: None, Single Rail Gas Block
Weight: 3.649 lbs