Supplementing your exisiting DISSENT® with another upper or looking to build a new bufferless AR? The 5.56mm DISSENT upper group with a 16.1 barrel is a hard choice to pass up. Pair with a mil-spec compatible lower receiver and the included 1913 Picatinny rear end plate you can add accessories like slings if you’re going for a pistol build or a folding stock if a compact carbine is more your style. – Utilizing our patent pending direct impingement Compact Action DISSENT upper groups house the entire action and recoil assembly in the upper receiver resulting in less bulk and length than traditional AR pistols. The forward non-reciprocating side charger allows for quick bolt operation without coming off target. Direct impingement DISSENTS come equipped with a left side charger standard. – All DISSENT Upper groups include a 1913 Picatinny rail end plate to use in place of the lower receiver buffer tube. – Adjustable Gas Block – If you’re looking to shoot suppressed or just fine tune your DISSENT to your preferred ammo the adjustable gas block gives you the freedom to dial in the gas system exactly to your liking. Never too much and never too little. – Platform Mk4 – Caliber 5.56mm – Operating System Compact Action-Direct Impingement – Barrel Length 16.1 – Barrel Twist 1:7 – Barrel Contour MT – Barrel Material 4140CM SBN – Barrel Twist 1:7 – Muzzle Device CMMG ZEROED Muzzle Brake – Muzzle Thread 1/2 x 28 – Gas Port Location Mid – Gas Block Adjustable 0.750 – Upper Receiver DISSENT 7075 T6 Aluminum – Hand Guard CMMG 15 Proprietary – Finish Cerakote – Charging Handle DISSENT Side Charger- Left – Receiver Extension 1913 Picatinny Rail End Cap – Weight 5.05 lbs – Length 25.5