Davidson Defense Quadratic 20-inch Rifle-Gas 1:7 22 ARC AR-15 Quad-Rail Handguard Rifle Upper Build Kit

Quadratic 20-Inch Rifle-Gas 1:7 .22 ARC AR-15 Quad-Rail Handguard Rifle Upper Build Kit

The Quadratic Upper Build Kit is built around a 20-inch .22 ARC Bear Creek Arsenal HBAR barrel with a rifle-length gas system and a 15-inch four-sided Picatinny quad rail handguard. BCG and charging handle are not included.

Key Features

• 20-inch Bear Creek Arsenal HBAR barrel, 1:7 twist, Black Nitride finish
• Rifle-length gas system
• 7075-T6 aluminum upper receiver with M4 feed ramps, anodized finish
• 15-inch free-float quad rail handguard, four-sided Picatinny rail system, black
• A2 GI Birdcage flash hider on 1/2x28 threads with 1/2-inch black crush washer
• BCG and charging handle are not included.

Barrel and Gas System

The 20-inch Bear Creek Arsenal barrel is machined in an HBAR heavy profile, carrying extra mass down its length to help manage heat and hold accuracy across longer strings of fire. It's finished in Black Nitride for wear and corrosion resistance, and its 1:7 twist rate is on the faster end for .22 ARC, giving it the stabilization needed for a wide range of bullet weights. The rifle-length gas system runs through a stainless steel gas tube and a micro low-profile steel gas block with a .750-inch diameter, matched to the barrel's .750-inch gas journal. At the muzzle, 1/2x28 threads carry the included A2 GI Birdcage flash hider, rated for .223 Remington and 5.56 NATO, and secured with the supplied 1/2-inch black crush washer.

Upper Receiver and Handguard

The upper receiver is machined from 7075-T6 aluminum with M4 feed ramps and an anodized finish, and it includes the forward assist assembly along with the ejection port door, rod, and spring. It's paired with a 15-inch free-float quad rail handguard finished in black, running a four-sided Picatinny rail system for mounting optics, lights, and other rail-mounted accessories.

Follow all manufacturer instructions and safe handling practices.

Ensure compliance with all applicable federal, state, and local laws.