
The Brownells BRN-180 was inspired by the Armalite AR-180, a civilian version of the AR-18 form the 1960’s. It was developed as a successor to the AR-15. The BRN-180 takes all the improvements of the AR-18/AR-180 platform and incorporates them into a modern upper.

It uses a robust and reliable gas piston operating system, and the carrier rides smoothly on two guide rods. It has a rear polymer buffer with a molded in steel plate to capture the guide rods.

This allows the use of folding stocks without losing the benefit of a buffer.

The bolt is a modern reproduction of the AR-180 bolt design, and even uses a standard AR-15 extractor per the original spec. Make no mistake, this retro design is a modern marvel. Overbuilt, reliable and amazing to shoot!
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From the Brownells website:
“The 16″ barrel is machined from extra-strong 4150 carbon steel, with a hard Nitride finish that really resists surface wear. The BRN-180 is chambered in .223 Wylde – for extra flexibility in ammo choice – with 1-8″ rifling, so it handles both .223 Remington and military-type 5.56mm NATO ammo with equal aplomb. Up front there’s a replica of the AR-180’s unusual three-prong flash hider: the hemispherical bottom prong helps prevent the muzzle blast from kicking up a dust signature when shooting prone. Standard ½-28 tpi muzzle threads let you swap on a modern AR-15 muzzle device should you be bitten by the customizing bug.”

Brownells BRN-180 Features:
- Ultra-reliable AR-180 piston operating system
- Compatible with current mil-spec AR-15 lowers
- Machined 7075 T6 aluminum receiver & handguard – hardcoat anodized finish
- 16″ barrel with matte black Nitride finish
- .223 Wylde chamber
- Button rifled bore; 1-8″ twist
- ½”-28 threaded muzzle
- Replica 3-prong AR-180 flash suppressor
- Molded polymer ejection port cover
- Total weight: 4.65 lbs

Also brought over from the AR-180™ design is the ease of removing the BRN-180 upper’s handguard. The recoil guide rods inside engage a U-clip that retains the handguard. When the bolt/carrier group is removed and the guide rods are pulled to the rear, the U-clip can be pulled down and the free-floating handguard assembly slid off!

With some effort to retain a period look, our BRN-180 handguard has modern M-LOK® slots and a full length Picatinny top rail that matches seamlessly to the receiver’s MIL-STD 1913 rail.

The BRN-180™ ships with a standard Piston Cup pre-installed. This Piston Cup is optimized for unsuppressed use. Also included is a Suppressor Piston Cup. When first shooting the BRN-180™ suppressed, you’ll want to try the Upper with the Suppressor Piston Cup installed. It vents gas earlier and in greater volume than the standard Piston Cup, and will smooth out the action. Some Suppressors and ammo combinations may run better with the standard Piston Cup, so give each a try.
The Brownells BRN-180™ Complete Upper Receiver delivers a unique combination of “Retro” nostalgia and a robust, reliable, AR-15 platform with the latest 21st Century upgrades. It’s proof that when you wait long enough, the old truly does become new again!”
The complete uppers are a direct fit and fully compatible with all standard mil-spec AR-15 lowers, so they are ready to go!

Here’s the parts breakdown for the build:
Upper – Brownells BRN-180 AR-15 Complete Upper Assembly

Lower – Anderson Manufacturing AR-15 Stripped Lower

Stock – Brownells AR-15 Mil Spec Collapsible Stock Assembly

Lower Parts Kit – CMMG AR-15 Lower Parts Kit

Grip – Magpul MOE+ AR-15 Grip

Trigger Guard – Magpul AR-15 Enhanced Trigger Guard

Magazine – Amend2 Mags

Magazine Extension – Amend2 Mags +5 Aluminum Extension

Sights – Troy Industries AR-15 Folding Battle Sights

Special Thanks to Brownells for photo and informational support!
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