The Adams Arms Mid-Length Gas Piston AR-15 complete upper assembly has everything you want in a piston upper assembly. The mid-length short stroke gas piston operating system is designed to run cooler and cleaner than a standard direct impingement system.

Piston systems increase overall reliability while also decreasing the amount of maintenance required to keep the firearm operational. This upper receiver can be connected to any standard AR-15 pistol lower receiver. This upper receiver is not pinned or welded.

Note: All NFA rules apply.

Features and Specifications:
Manufacturer Number:UA-14.5-M-B-556
AR-15 Complete Upper Receiver
Caliber: 5.56mm NATO/.223 Remington
Barrel: 14.5", Government Profile, 4150 Chrome Moly Vanadium Steel With QPQ Melonite And Black Nitride Barrel Finish (Not Chrome Lined)
Rifling: 1:7" Twist
Muzzle: 1/2"x28 Threading
Muzzle Device: A2 Flash Hider
Handguard: 2-Piece Polymer Construction, Mid-Length
Gas System: Mid-Length Short Stroke Piston Operated
Gas Block: .750" Dia, Railed
Bolt Carrier: 1-Piece Integral Piston Strike Face
M4 Feed Ramps
Weight: 4 lbs