Brn-4(R) Complete Upper Receivers - Brn-4 5.56mm 10.4'''' Heavy Bbl Complete Upper W/9'''' Handguard
Click to see full view
Brownells
Overview
The Brn-4(R) Complete Upper Receiver from Brownells features a 10.4-inch barrel chambered in 5.56 NATO, designed for use on the AR-15 platform. This complete assembly includes a heavy barrel that enhances durability and accuracy, making it suitable for a variety of applications. Builders typically use this upper in compact builds where maneuverability and reliability are key considerations.
Specifications
Brn-4(R) Complete Upper Receivers - Brn-4 5.56mm 10.4'''' Heavy Bbl Complete Upper W/9'''' Handguard
Build history on GunPartPicker
Builders on GunPartPicker first added the Brownells Brn-4(R) Complete Upper Receivers - Brn-4 5.56mm 10.4'''' Heavy Bbl Complete Upper W/9'''' Handguard to a build in April 2026.
It was out of stock everywhere we track for all of September 2026, and today the one retailer we track is out of stock. Listed prices start at $1,299.99 at Brownells for when it comes back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 30+ retailers
Not sure which upper receiver to pick?
We ranked every upper receiver by how often it shows up in real builds on GunPartPicker.
Read the guide: Most Popular AR-15 Upper Receivers →Check it against the live catalog:
Frequently Built With
Popular alongside upper receivers on GunPartPicker
Aero Precision M4E1 Complete Lower Receiver W/MOE SL Grip & SL-S Carbine Stock
Aero Precision AR-15 Breach Charging Handle Ambidextrous Small Levers
Geissele Automatics AR-15 SSA-E X Lightning Bow Trigger
Bravo Company M16 Bolt Carrier Group Black
Magpul AFG-2 Angled Fore Grip - Black
Magpul AR-15 MOE Stock Collapsible Mil-Spec Black
No reviews yet. Be the first to review this product!