The Brownells BRN-PROTO® is a faithful reproduction of Eugene Stoner’s original AR-15 prototype, built to replicate the configuration of the earliest Armalite design. The rifle is chambered in 5.56x45mm NATO and .223 Remington compatible, with a 20-inch barrel cut with a 1:12 twist. The gas system is rifle length, and the bolt carrier group is chrome plated.

Both the upper and lower receivers are forged and machined from 7075-T6 aluminum with a matte gray anodized finish to replicate the period-correct appearance. The rifle is delivered with one 25-round magazine, a GI-style operations manual, and a chamber flag.

Specifications:

• Manufacturer: Brownells

• Model: BRN-PROTO® (Retro Prototype)

• Caliber: 5.56x45mm NATO / .223 Remington

• Barrel Length: 20 in

• Twist Rate: 1:12 in

• Gas System: Rifle length

• Receiver Material: Forged/machined 7075-T6 aluminum

• Finish: Matte gray anodized

• Bolt Carrier Group: Chrome plated

• Magazines: 1 25-round magazine

• Accessories: GI operations manual, chamber flag

• Overall Length: ~39 in

• Weight (Unloaded): ~6.5–7 lb