BCM® SS410 20" Complete Upper Receiver Group w/ KMR-A15 Handguard

MSRP: $901.95
Your Price: $813.95
(You save $88.00 )
Maximum Purchase:
5 units
5.56 NATO
Barrel Length:
Barrel Style:
Stock Status:

About the BCM® SS410 20" Complete Upper Receiver w/ KMR-A15 Handguard

All BCM® Upper Receiver Groups with a KMR-A Handguard Include:

  • One 3" Picatinny Rail Section
  • One BCM KeyMod Sling Mount

Manufactured by Bravo Company MFG, Inc. (BCM)

These Barreled Upper Receiver Groups are designed for shooting professionals and responsible civilians with the Mil-Spec features for the demands of their duty. They are fully assembled, headspaced, and test fired.
As a note: Prior to shipping, all BCM upper receiver groups are test fired for function, laser bore sighted with a Milspec carry handle for sight alignment within Mil-Specs, and then batch samples are test fired for accuracy. As such, the upper receiver group will show handling marks consistent with these quality control procedures.

SS410 Barrel Steel

This 20" BCM barrel is machined from SS410 stainless steel. Featuring hand lapped 1/8 twist rate button rifling and M4 feed ramps barrel extensions, the 410 stainless barrel gives the shooter the best balance of weight and accuracy. 410 stainless is also harder and more corrosion resistant than conventional 416 stainless found in other commercially available precision barrels.

M4 Feed Ramp Barrel Extension and Upper Receiver

In developing the USGI M4 carbine as one of the primary weapons for today's infantry, some modifications were performed to the original M16 platform to enhance the reliability of the shorter barreled carbines. With the shorter carbine gas system and the increased gas port pressure, the carbine cycled faster, and at times the cycle rate could be faster than the magazine would feed ammunition. One of the modifications done to increase reliable feeding included enhancing the angle and the length of the feed ramps.
This USGI modification was done to both the barrel extension and the upper receiver, creating a longer and steeper feed ramp. These Mil-Spec M4 feed ramps are part of the original CNC manufacturing process. As a result, the factory machined M4 feed ramps on the receiver are hard coat anodized which adds significant strength to the aluminum. This feature is offered on all BCM upper receivers and all BCM barrels.

T-Marked Upper Receiver

The contemporary M16/M4 rifle is built around the concept of modularity. All of the BCM flat top uppers feature a USGI type laser etched T-marks to provide addressing for the remounting of tactical accessories such as optics, laser sights, etc. This enables the weapon platform to be easily configured and then accurately reconfigured for each specific mission.

5.56 NATO Match Chamber (USMC SAM-R Chamber)

The USGI 5.56 NATO chamber is the best choice for effective deployment, reliability, and compatibility, of higher chamber pressures of military or high quality personal defense ammounition.  The SAM-R chamber is the precision version of the 556 NATO chamber.

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.***

15 Reviews

  • 5
    Outstanding !!

    This upper was my first BCM purchase. The fit and finish of it was very good. took it out last week paired with a leupold mark ar 4-12 optic and was printing 1-1.5 MOA out of the box using PMC 55 grain!!!!!! also love all the swag that came with!!!
    Thanks BCM for offering such a great upper and excellent service!!!

  • 5
    SS410 20" upper

    Ordered my upper on Sunday and had it Friday. That's was fast, "A" for service. The fit on my Anderson 80% lower I built is perfect. I spent a fair amount of time reading reviews and talking to people before building this ar. There are many manufacturers to choose from some quality some not, BCM definitely is quality. I chose them for this and their reputation for great customer service. Haven't had a chance to take it to the range yet, but can't wait. I do wish you guys did custom work. Wanted my barrel painted dark earth, Maybe in the future. If I build another at it will definitely be with BCM products. Thank you guys!

  • 5
    Great upper

    shoots great ,well made and fast shipping

  • 5
    HooYAH Bravo COmpany

    My one stop shop for quality parts and excellent service. I never hesitate to buy from Bravo Company.

  • 5

    Well what else can be said about BCM, fast shipping great looks and a real head Turner this 20" SS rifle will be. Thanks again BCM

  • 5
    BCM SS410 20" Upper Receiver Group w/ BCM KMR- *A

    I ordered ss410 20' upper group from BCM on wed at lunch break (1pm) on work and got the call that it was at my house Thursday at 10 am! less than 24 hours! too bad I didn't order the rest of my parts from BCM. I'm now forced to stare at this beautiful upper just sitting on a shelf for a week and a half.