User Ratings
No ratings yet
Be the first to review this product
BRN-4 Upper Receiver Assemblies are AR-15 upper receivers assembled with barrel and gas system installed. The upper includes a Magpul ejection port cover and mil-spec charging handle. Barrels are chambered in 5.56x45mm NATO with a 1:7 twist and 1/2-28 muzzle threads, available in medium or heavy contours. The upper is machined from billet 8620 and finished with matte black hard coat anodizing. Gas blocks are matched to the chosen barrel length. Upper includes a piston bushing and torqued barrel nut assembly for a robust platform.
Specifications
- Manufacturer:
- BRN-4
- Category:
- upper-receiver
- Platforms:
- AR-15
- Interfaces:
- Muzzle thread: 1/2-28
- UPC:
- 050806500655
- MPN:
- BRN-4-16-UPPER- HVY BBL
- Required Component:
- Yes
Parts Cabinet
Track parts you own or plan to buy.
Where to Buy
Have one to sell?
Sponsored
MantisX
The smart way to train your AR build
Built your rifle — now train it. BlackBeardX installs in minutes and turns your AR into a full dry fire system with smart feedback on every pull.
Shop BlackBeardXPrice History
Current
$1,199.99
Lowest
$1,024.99
Highest
$1,199.99
Price Alert
Sign in to save a target price and receive an email when this component drops.
Sign In to Set AlertWhat's Included in this Bundle
Similar Products
Bravo Company BCM4 Upper Receiver Assembly Flat Top With Forward Assist 1913 Rail
Bravo Company Manufacturing (BCM)
$129.00
Aero Precision AR15 Assembled Upper Receiver - Anodized Black - APAR501603AC
Aero Precision
$118.99
LMT Monolithic Upper Receiver - AR-15 - MRP-L - M-LOK - Specwar - 11.5"
LMT
$912.60
Griffin Armament Mk1 Upper Receiver Assembled Aluminum Black
Griffin Armament
$113.95
Bravo Company 4URM4 BCM M4 Upper Assembly Multi-Caliber 7075-T6 Aluminum Black Anodized Receiver for AR-15
Bravo Company Manufacturing (BCM)
$137.04
BCM MK2 Carbine Barreled Upper MCMR-10 - 12.5in
Bravo Company Manufacturing (BCM)
$820.39
AERO PRECISION - 5.56X45 NATO ASSEMBLED UPPER RECEIVER NO AUTO SEAR CUT FOR AR-15
Aero Precision
$119.99
COLT Monolithic AR-15 Pistol Complete Upper Receiver 5.56x45 NATO 11.5" Barrel
Colt
$959.99
Builds Using This Part
No builds yet — be the first to use this part.
Related Guides
Guide
5.56 NATO, .223 Remington, and .223 Wylde: Chamber Differences Explained
A technical breakdown of the differences between 5.56 NATO, .223 Remington, and .223 Wylde chambers — what each accepts safely, and how to choose for your build.
5 min read
Guide
AR-10 Receiver Patterns: DPMS vs. Armalite Compatibility
The AR-10 has two incompatible receiver patterns — DPMS and Armalite — that look similar but do not share parts. This guide explains the differences and how to buy correctly.
6 min read
Guide
The AR-10 Platform: What It Is and How It Differs from the AR-15
A practical overview of the AR-10 — its origins, how it differs from the AR-15, available calibers, and when it makes more sense than a standard AR-15 build.
6 min read