Maxim Defense PDX Upper .300 AAC Blackout 5.5-inch FDE

The Maxim Defense PDX upper is a complete .300 AAC Blackout upper designed for installation on any Mil‑Spec lower receiver. It features a 5.5-inch barrel and a flat dark earth matte finish. The assembly uses a direct impingement gas system and includes Maxim's HATEBRAKE muzzle booster, a patent-pending muzzle device intended to reduce recoil and flash signature.

Key Specifications

• The barrel measures 5.5 inches for compact handling.
• The caliber is .300 AAC Blackout.
• The finish is Matte in a Flat Dark Earth color.
• The model is listed as PDX.
• The system uses a Direct Impingement gas operation.
• The muzzle device is the Maxim HATEBRAKE Muzzle Booster (patent-pending).
• It is a complete Upper intended for installation on a Mil‑Spec lower receiver.
• The product's overall length is 14 inches, as stated by the manufacturer.

Compact and purpose-built, the PDX upper suits shooters seeking a short-barrel AR configuration with .300 AAC Blackout capability, reduced muzzle impulse, and a professional FDE finish suitable for range use, compact builds, or personal defense applications.