Brownells Brownells Brownells 75th Anniversary - A Shooting Heritage

Enhanced upper receiver is everything you need to convert your AR carbine or pistol to the exciting new 300 AAC Blackout (300 BLK) round. Features a nitrided, 1-7 twist barrel with M4 feed cuts, a Knight’s Armament URX free-floating handguard, and AAC'S 51T flash suppressor. 51T accepts the AAC 762-SDN-6 sound suppressor to make the gun nearly silent when used with subsonic ammunition. The nitride treated bore and chamber provide excellent corrosion resistance and a longer service life than standard chrome-lined barrels, and the full-profile M16 bolt/carrier group allows these uppers to function on a full-auto M16 lower as well as on semi-auto guns. Available with standard 16" Carbine and 9" Pistol barrels, designed to function with subsonic and supersonic ammunition. All barrels feature a 1-7 twist.

MPW 5.56 Upper Receiver

  • 5.56 NATO Complete upper receiver for AR-15/M16 platforms
  • 16” Nitrided 4150 CMV steel barrel
  • M4 feedramps
  • Includes AAC 51-tooth Blackout Flash Suppressor
  • Knight’s Armament free-floating URX rail
  • M16 Bolt Carrier Group
  • Bolt is Carpenter 158 steel and includes improved extractor o-ring
  • Internally chrome lined bolt carrier
  • Heat-treated gas-key with proper staking
  • Full auto chamber dimensions
  • Carbine length gas system
  • Charging handle included

AR-15, Issue:11, Page:009
Brownells Christmas , Issue:3X, Page:021
Big Book Catalog, Issue:68, Page:009

SPECS: Receiver – Aluminum, M4 Feedramps, Picatinny Top Rail, Matte Black Anodizing, M16 Bolt Carrier Group. Handguards –Freefloat URX II (12.5" and 16”) or URX III (9”). Barrel – 16” or 9” nitride 300 Blackout, 5/8-24 threaded muzzle, 1-7 twist, 51T Blackout Flash Hider.

The 9" AAC 300BLK Uppers are designed for use with a carbine receiver extension, standard GI Buffer Spring, and an H2 Buffer.

The 16" AAC 300BLK Upper is designed for use with a carbine receiver extension, standard GI Buffer Spring, and a CARBINE Buffer.

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101716  16" AR UPPER 300 BLK
16" AR Upper 300 BLK
27600001116" AR Upper 300 BLK

Mfr Part: 101716


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In Stock

Cartridge: 300 AAC Blackout

Finish: Matte Black

Length: 16

Style: Complete

Twist: 1-7

Other Matches

16" AR Upper 5.56
27600004316" AR Upper 5.56

Mfr Part: 102780


Online Only
Out of Stock

Cartridge: 5.56 mm NATO

Finish: Black

Length: 16

Style: Complete

Twist: 1-7