Davidson Defense Heirloom 14.5-inch Carbine-Gas 1:7 5.56 NATO AR-15 M-Lok Pistol Complete Upper Build

Heirloom 14.5-inch 5.56 NATO AR-15 Complete Upper

The Heirloom is built around a 14.5-inch 5.56 NATO barrel with an M4 profile, finished in Parkerized. It's paired with a 7000 Series optimized AR-15 upper receiver finished in Type III hardcoat black anodizing. It pairs a 12-inch Air Lite Series "Honeycomb" free-float M-LOK handguard with an A2 GI birdcage flash hider at the muzzle, running on a carbine-length gas system. A complete bolt carrier group and Mil-Spec charging handle round out the upper, giving the buyer everything needed on the upper side.

Key Features

• 14.5-inch 5.56 NATO barrel, 1:7 twist, M4 profile, Parkerized finish
• Carbine-length gas system with micro low-profile steel gas block
• 7000 Series optimized AR-15 upper receiver, Type III hardcoat black anodized
• Air Lite Series "Honeycomb" 12-inch free-float M-LOK handguard, monolithic Picatinny top rail
• A2 GI birdcage flash hider
• Complete bolt carrier group and Mil-Spec charging handle included

Barrel and Gas System

The barrel runs 14.5 inches long, chambered in 5.56 NATO and built from 4150 chrome moly vanadium steel with a Parkerized finish and M4 profile. It carries a 1:7 twist rate and a 1/2x28 muzzle thread. Gas cycles back to the action through a carbine-length system, running a carbine-length stainless steel gas tube and a micro low-profile steel gas block sized to a .750-inch journal.

Upper Receiver and Handguard

The upper receiver is a 7000 Series optimized AR-15 unit finished in Type III hardcoat black anodizing, featuring a dust cover pin feature and a flat-top Picatinny rail. The ejection port carries a standard .223/5.56 door with its rod and spring installed. Over the barrel sits a 12-inch Air Lite Series "Honeycomb" handguard, free-floated and using an M-LOK attachment system with a monolithic Picatinny top rail running along its length.

Muzzle Device

Capping the muzzle is an A2 GI birdcage flash hider, threaded to match the barrel's 1/2x28 pattern and secured with the included 1/2-inch black crush washer.

Bolt Carrier Group and Charging Handle

A complete AR-15 bolt carrier group is included, made in the USA and listed for use across 5.56 NATO, .223 Remington, .300 Blackout, and .350 Legend. That broader listing describes the BCG itself; the barrel and chambering on this upper remain 5.56 NATO. A Mil-Spec AR-15 M4 charging handle rounds out the upper's operating components.

Follow all manufacturer instructions and safe handling practices.

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