Davidson Defense IX w/Magpul BTR Brace 8.3-inch 1:10 9MM AR-9 Freefloat M-Lok Handguard Pistol Full Build Kit

IX 8.3 Inch AR-9 Full Build Kit 9mm Freefloat MLOK with Magpul BTR Brace

The IX AR-9 Full Build Kit is a complete pistol build package centered on an 8.3 inch 9mm barrel made from 4140 gun steel with a Nitride finish and a medium profile, carrying a 1:10 twist rate. The upper receiver is a billet design machined from 6061-T6 aluminum with a Type III hardcoat anodized finish, paired with a 10 inch MLOK freefloat handguard made from aluminum in black. This kit includes a complete bolt carrier group, charging handle, and a Magpul BTR pistol brace.

Key Features

• 8.3 inch 9mm barrel, 4140 gun steel, Nitride finish, medium profile
• 1:10 twist rate, 1/2x36 thread pitch
• 9mm flash can, manganese phosphate finish, 1/2x36 thread
• Billet 6061-T6 aluminum upper receiver, Type III hardcoat anodized finish
• 10 inch MLOK freefloat handguard, aluminum, black
• 9mm Nitride bolt carrier group, 8620 alloy steel
• Mil-Spec quality M4 charging handle
• Buffer weight 5.5 oz
• Magpul BTR pistol brace, black, polymer, for standard Mil-Spec buffer tube

Perfect For

• Builders assembling a 9mm AR-9 pistol platform from the ground up
• Shooters wanting a billet upper paired with a freefloat MLOK handguard
• Builders looking for a matched bolt carrier group and brace in one kit

Barrel and Operation

This kit uses an 8.3 inch barrel made from 4140 gun steel with a Nitride finish and a medium profile. The 1:10 twist rate is suited to 9mm bullet weights, and the 1/2x36 thread pitch matches the included flash can, finished in manganese phosphate. This build operates on a blowback system.

Upper Receiver and Handguard

The upper receiver is a billet design machined from 6061-T6 aluminum and finished in Type III hardcoat anodize. A 10 inch MLOK freefloat handguard made from aluminum in black surrounds the barrel without contacting it, giving the upper assembly a compact exterior forend built for a short pistol length platform.

Bolt Carrier Group, Charging Handle, and Brace

The included bolt carrier group is made from 8620 alloy steel with a Nitride finish, paired with a buffer weighing 5.5 oz. A Mil-Spec quality M4 charging handle rounds out the upper side component set. A Magpul BTR pistol brace in black polymer, built for a standard Mil-Spec buffer tube, is included as part of this build kit.

Follow safe handling and manufacturer instructions.

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

Component specifications are subject to the details provided in this listing.