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Manufactured in the US with the highest quality components, the BRN-15 Upper Receiver Groups are great starts for your next build. Pick your preferred bolt carrier group and charging handle to complete.
The BRN-15 Upper Receiver Groups feature a 5.56x45mm NATO chambered, nitride finished barrel, available in several popular lengths. Models are available in a Government, medium profile barrel, with the 16 inch also available in a lightweight contour. Barrels feature a gas block dimple, that the rear gas block screw securely engages. All barrels are stress releived.
Unique MLOK handguard extends past the gas block, to provide as much usable real estate as possible. Anti-rotation tabs at the rear of the handguard engage the upper receiver, preventing any cant in relation to the receiver picatinny rail. Large dual screws clamp and pass through the properly torqued barrel nut to ensure the handguard will not slip forward. Large vents are placed towards the rear, to allow both the barrel and handguard to cool more rapidly.
Forged Mil-Spec type upper receiver features M4 feed ramps, ejection port cover and forward assist. Forward assist pin is knurled at the front, to ease future swaps.
- 4150 CMV (Chrome Moly Vanadium) Barrel
- Chambered in 5.56x45mm NATO
- 1-7 Barrel Twist
- 1/2-28 Muzzle Threads
- A2 Flash Hider
- Forged 7075-T6 Upper Receivers
- Hardcoat Anodized Upper Receiver
- M4 Feedramps in Upper & Barrel Extension
- Barrels are marked "5.56 NATO 1:7 4150CMV SR"
- 100% American Made
Please note, the 16 inch lightweight features a lock nut on the muzzle device. To remove, secure the lock nut with a wrench, turn towards the rear, and unscrew the flash hider.
All NFA Rules Apply.
Specifications
- Manufacturer:
- Brownells
- Category:
- upper-receiver
- Caliber:
- 5.56x45mm NATO
- Platforms:
- AR-15
- Weight:
- 25 oz (1.56 lbs)
- Length:
- 8.0" - 9.0"
- UPC:
- 050806000223
- MPN:
- 4027-3410-B1
- Required Component:
- Yes
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