DoubleStar AR-15 Complete Pistol Upper Assembly .300 Blackout 7.5″ Barrel 1:8 Twist Free Float Handguard Black ARBU240C


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DoubleStar 7.5″ .300 Blackout AR Pistol Upper Complete, Heavy Barrel, with M-4 Feed Ramps, 1×8 twist

This DoubleStar AR-15 Upper Receiver Assembly in 300 AAC Blackout is a pin-on, ready-to-shoot top end for use with any legally registered SBR or dedicated pistol AR-15 lower receiver. The Mil-Spec 7.5” 4140 steel black nitride coated barrel comes equipped with 1 in 8″ twist rifling, M4 feed ramps, and a DoubleStar picatinny rail gas block. The muzzle is threaded with a 5/8″-24 pitch for easy installation of a silencer, and is topped off with an effective A2 flash hider.

The upper features a hard coat anodized A3 flat-top receiver with a DoubleStar pistol length free-floating handguard, T-Marks, forward assist, and dust cover. The The DoubleStar Upper includes a standard AR-15 semi-auto bolt carrier, properly staked gas key with MPI bolt assembly.

This 7.5″ 300 Blackout upper utilizes a pistol length gas system and is compatible with most subsonic and supersonic ammunition, with or without a sound suppressor in place. However, some subsonic ammunition may not always cycle reliably under adverse conditions or in a severely fouled firearm without a sound suppressor attached to provide extra backpressure.

Features and Specifications:
Manufacturer Number: ARBU240C
Upper Receiver: A3 Flat-Top
Barrel Length: 7.5″
Barrel Contour: HBAR
Barrel Material: 4140 Steel
Muzzle Thread Pattern: 5/8″-24
Chrome Lined: No
Barrel Finish: Black Nitride
Twist Rate: 1 in 8″
Chamber: 300 AAC Blackout
M4 Feed Ramps: Yes
Muzzle Device: A2 Flash Hider
Gas System Length: Pistol
Gas Block Diameter: 0.750″
Handguard: Pistol Length, 6061-T6 Aluminum, Free Floating
Sights: None
Bolt Carrier Assembly Included: Yes
Bolt Carrier Type: Commercial
Suitable for use w/Subsonic or Supersonic loads, either Suppressed or Unsuppressed
Compatible w/standard AR-15 magazines, including Magpul Pmags (Not Included)

Please Note: An “AR-15 Pistol” upper assembly has a barrel less than 16” in length. Pistol uppers are only for use on AR-15 pistol lowers and legal Short-Barreled Rifles. Other configurations may violate Federal law. Installation of AR-15 upper assemblies with certain features including, but not limited to: flash hiders, bayonet lugs, and threaded muzzles may violate state and/or local laws.

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