BCM® Standard 7" 300 BLACKOUT Complete Upper Receiver Group w/ MCMR-5 Handguard

MSRP: $1,059.50
Your Price: $769.00
(You save $290.50 )
Maximum Purchase:
10 units
300 BLK
Barrel Length:
Barrel Style:
Stock Status:

Out of stock

About the BCM® Standard 7" 300 BLACKOUT Complete Upper Receiver w/ MCMR-5 Handguard

  • Continuous taper barrel profile designed for optimal weight, balance, and performance.
  • 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

  • MCMR-5 Handguard
  • MCMR-SM (MCMR Sling Mount)
  • One 3" Picatinny Rail Section
  • 7.62/300BLK Flash Hider

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 High Velocity ammo only with a H3 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: 7"
  • 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: 762/300BLK Flash Hider
  • Muzzle Threads: 5/8x24
  • Handguard: MCMR-5

Shop Related Products:

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


Bravo Company builds: Life Saving Tools™
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.***

7 Reviews

  • 5
    Same Great Quality As Usual

    Perfect fit onto my BCM RECCE 16 AR lower converting it to 300 Blkout. Slapped on a Law Tactical collapsible stock attachment and a pistol brace to stay legal. Shot it the other day and it's simply OUTSTANDING!

    Amazing BCM quality as usual, nothing much to say other then get one if you can!!!

  • 5
    7” 300 Blackout Upper

    Really excited about this upper. Fit and finish is excellent. Paired it with a Noveske Gen 3 Lower. Installed a Surefire 3 prong flash hider. Still waiting on my Form 4 but I got a Surefire SPS 300 suppressor for this build. It’s going to be beautiful haha.

  • 5
    Fit and function

    Have not fired a shot yet! Waiting for suppressor and building the pistol lower but by the looks of everything, it’s clearly going to make a solid subsonic suppressed pistol build !

  • 5
    Best AR Pistol

    Great AR Pistol build. Paired with a BCM pistol lower with SBA3 brace and Law Tactical Folder. Primary Arms GLX 2X Prism for 300 Blackout. Utilized H3 buffer.

    Shot this at the range today and it ran very well. I shot 123gr MagTech and 147gr Bernaul. I used Lancer Mags for 300 BLK.

    Thanks BCM for an amazing build.

  • 5
    Excellent Product

    This 300 Blackout is fantastic. My new favorite weapon system. It is now a complete BCM Short Barrel Pistol. Primary Arms 300BLK ACSS 2X Prism. Dueck Defense Offset Iron Sights. Law Tactical Folding Stock Adapter. SB Tactical SBA3 Pistol Brace. Blue Force Gear 2 Point Sling. Strike Industries Angled Foregrip. This piece is one sweet ass pistol. Thanks BCM for everything.

  • 3
    BCM Standard 7” 300 BLK complete upper receiver, MCMR-5 Handguard

    I really expect to purchase this particular complete upper with MK2 upper receiver , because I wish to suppress this upper , and MK2 upper receiver should be originally deliver together . I am very proud owner of few BCM product including my BCM 11.5 in 5.56 pistol

  • 5
    Excellent Product

    This 7" 300BLK upper receiver group is fantastic, its lightweight, damn short, and extra fun to shoot. I love this gun for vehicular defense and close quarters battle. It is designed to be suppressed. So, I am still waiting on my Yankee Hill Machine 'The Resonator' K, .30 Cal to be approved. With this CAN it will become "whisper hollywood quite" when firing 220 grain subsonic rounds. This upper is perfectly merged with my BCM lower receiver group with zero tolerance. I am also rocking a Law Tactical Butt-Stock Folder on it to make it more compact and transportable inside of my gym bag if I need it. I also have a Primary Arms 2X 300 BLK ACSS Prism. This is absolutely my favorite short barrel pistol. It stays by my bedside ready to go and whenever I travel it goes with my in my rig for long distance driving. Thanks BCM.