BCM® Standard 9" 300 BLACKOUT Complete Upper Receiver Group w/ KMR-A8 Handguard

MSRP: $1,059.50
Your Price: $781.45
(You save $278.05 )
Maximum Purchase:
5 units
300 BLK
Barrel Length:
Barrel Style:
Stock Status:

Out of stock

About the BCM® Standard 9" 300 BLACKOUT Complete Upper Receiver w/ KMR-A8 Handguard


  • Continuous taper barrel profile designed for optimal weight, balance, and performance.
  • Barrel profile fluted toward the rear near chamber area - Increases strength and heat dissipation.
  • Tapered barrel profile out front, for easier maneuverability.
  • No sharp handguard cap shoulder for improved barrel harmonics and improved accuracy.
  • Muzzle threaded in standard 30 cal (5/8x24).

Whats included with this complete upper:

  • KMR-A8 KeyMod™ Handguard.
  • KMSM (KeyMod™ Sling Mount)
  • One 3" Picatinny Rail Section
  • BCM® Comp Mod 1 - 762/300 BLK

BCM® has taken great care to ensure the best possible performance and interchangeability. However, due to the large operational range of 300 Blackout ammunition in the market place, BCM® cannot guarantee function will all ammunition types in all conditions. These barrels were designed to run with a H3 buffer with high velocity ammo.

If running subsonic ammunition, it is recommended to run your suppressor and a carbine buffer. Fine tuning may be required in limited instances based on ammo and buffer choices that work best for the desired application. BCM® also recommends running the Crane O-ring (provided with all BCM® Bolt Carrier Groups) over the extractor with 300 Blackout.


  • Caliber: 300 Blackout
  • Barrel Length: 9"
  • Barrel Material: 11595E Spec Steel
  • Barrel Finish: Manganese Phosphate (Mil-Spec A-A-59267)
  • Bore & Chamber: Chrome Lined
  • Weight: 2.2 lbs
  • Twist Rate: 1:7
  • Gas System: Pistol
  • Muzzle Device: BCM® Comp Mod 1 (762/300BLK)
  • Muzzle Threads: 5/8x24
  • Handguard: KMR-A8

Shop Related Products:

Want to see more upper receivers? Click the links below to view more BCM® AR complete uppers!


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Copyright 2023 Bravo Company MFG, Inc.
***This product contains chemicals/materials known to the State of California to cause cancer and other reproductive harm. To learn more, visit www.p65warnings.ca.gov.***

131 Reviews

  • 5
    9in .300 blk

    Great upper fit and finish is perfect and it's an amazing lil shooter very happy went with BCM.

  • 5
    Rugged and reliable

    Once again I couldn't be happier with BCM. The quality and reliability is enough but the customer service puts them over the top. Not my first BCM build and won’t be my last.

  • 5
    Customer review

    Review body is empty

  • 5
    50 yd zero/200 yd shots

    50yd zero was 3/4 moa after final siteing / at 200 yds I was at 1.75 MOA one group was .75 MOA, that's insane! Extremely happy with that out of a 9" barrel using Primary Arms 3x Prism that wasn't very easy at 200 yds. GREAT RIFEL!

  • 5
    Great Upper

    Flawless so far. I love it!

  • 4
    A visual beauty

    Bought this upper for my first AR Pistol and my first 300blk. Visually it's a beauty and lite af, this is my 3rd BCM upper and they never disappoint. Just wish they did the FH/MB option besides just the BCM brands. Can't wait for my vacation to get it to the range and pop off a few rounds.

  • 5
    Great accuracy

    I didn't buy this upper to shoot 100 yard groups but when I did I was very surprised at the results! It shot consistent 3/4 inch groups at 100 yards with quality hunting ammo and about 1 1/4 with bulk ammo.

    Like all BCM products, this is a high quality upper and worth every penny!

  • 5
    Excellent so far

    I already own Colt and Daniel Defense rifles, after much research and recommendations decided to give BCM a try. Excellent performance so far (only a couple hundred rounds). It is lighter than I expected, finish and assembly is flawless, very fast shipping and excellent customer service I will definitely buy from BCM again and would recommend them to anyone considering.

  • 5
    300 shorty

    Love this 300blk k-mod upper. Exactly what I was looking for. Ergonomic and perfect fit.