Davidson Defense Aegis 5-inch 1:16 45ACP AR-45 Freefloat M-Lok Handguard Pistol Upper Build Kit

Aegis 5-inch .45 ACP AR-45 Upper Build Kit

The Aegis is a 5-inch .45 ACP AR-45 Upper Build Kit built around a slim-profile barrel and a pistol-caliber AR-15 billet upper receiver. It pairs a 4-inch ultra-lightweight minimalist handguard with a KAK Industry Micro Flash Can at the muzzle, giving this build a compact, front-heavy-free profile. The whole system runs on direct blowback, so there's no gas block or gas tube anywhere in the build. BCG and charging handle are not included, leaving the buyer to supply those components separately.

Key Features

• 5-inch .45 ACP barrel, 1:16 twist, slim profile
• Direct blowback operating system, no gas block or gas tube required
• Pistol-caliber AR-15 billet upper receiver
• 4-inch ultra-lightweight minimalist K-style free-float handguard
• KAK Industry .45 ACP Micro Flash Can muzzle device
• BCG and charging handle are not included.

Barrel and Muzzle Device

The barrel runs just 5 inches long, chambered in .45 ACP and built from 4150 chrome moly vanadium steel with a Parkerized finish. It's cut to a slim profile, keeping the front of the build light, and carries a 1:16 twist rate with a 37/64x28 muzzle thread. At the muzzle sits a KAK Industry Micro Flash Can chambered for .45 ACP, threaded to match at .578x28 and secured with the included 5/8-inch black crush washer.

Upper Receiver and Handguard

The upper receiver is a billet unit built for the pistol-caliber AR-15 platform this kit is designed around. Over the barrel sits a 4-inch handguard in a K-style, ultra-lightweight minimalist profile, keeping this already-compact build slim and light up front. It's M-LOK compatible along its length for mounting lights, grips, or other small accessories. This handguard skips anti-rotation tabs, so it relies on its mounting hardware alone to stay indexed.

Follow all manufacturer instructions and safe handling practices.

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

BCG and charging handle are not included.