Aero Precision M4E1 Threaded Barreled Upper Receiver 5.56 Mid-Length - ATLAS R-ONE - 14.5" - FDE

Aero Precision M4E1 Threaded Barreled Upper Receiver 5.56 Mid-Length - ATLAS R-ONE - 14.5" - FDEThis complete upper includes our new ATLAS R-ONE Handguard! The R-ONE handguards are designed with size and weight in mind, while still providing plenty of real-estate to accommodate any attachment needs the end user may have. Aero Precision's proprietary ATLAS attachment system is a durable and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have grown to love from Aero Precision handguards. This complete upper does not include a BCG or Charging Handle. Shop our current in-stock BCG's HERE and Charging Handles HERE.Includes:M4E1 Threaded Assembled Upper ReceiverATLAS R-ONE Handguard of choice14.5" 5.56 Mid-Length CMV BarrelLow Profile Gas Block and Mid Length Gas TubeProduct comes assembledThe muzzle brake that comes with the complete upper receiver is NOT pinned, nor welded, to this barrel. Per the National Firearms Act, the muzzle breake MUST be pinned and welded to achieve the necessary 16" as defined by the ATF for a rifle build.M4E1 Threaded Upper Receiver Features:New enhanced forging that gives the upper receiver a "billet look"New picatinny profile that blends seamlessly with our Enhanced Series HandguardsM4 Feedramps.250 takedown pin holesLaser engraved T-marksIncludes port door and forward assist installedATLAS R-ONE Handguard Features:Full top picatinny rail for optional attachmentsQuick disconnect sling socket at the 3, 6 and 9 o'clock positionsCompatible with low profile gas blocks1.3" Inside diameter1.5" Outside diameterCompatible with mil-spec AR15 upper receivers and barrels14.5" 5.56 Mid-Length Barrel Features:Chamber: 5.56Length: 14.5"Twist: 1 in 7Threading: 1/2"x28Material: Chrome Moly VanadiumFinish: QPQ corrosion resistant finish both inside and outGas Block: .750Gas Port: .0785Gas SystemSpecifications:Caliber/Gauge: 5.56x45Action: Semi AutomaticBarrel Length: 14.5"Barrel Twist: 1:7Barrel Finish: QPQ Corrosion ResistantFirearm Fit: AR-15Threaded Barrel: YesCondition NewSegth: MidWeight: 26ozM4 Barrel ExtensionHP and MPI Tested