Davidson Defense 9990 6" 9MM AR-9 Quad-Rail Complete Upper Build with Naughty 9 Suppressor

9990 6-Inch 1:10 9MM AR-9 Quad-Rail Pistol Complete Upper Build with Witt Machine The Naughty 9 Suppressor

This is a complete AR-9 upper assembly built for 9mm pistol-caliber performance. It pairs a 6-inch nitride barrel with a free-float quad-rail handguard and includes a Witt Machine The Naughty 9 suppressor. The upper receiver is billet aluminum, the barrel twist is 1:10, and everything threads at 1/2x28 for suppressor compatibility. This is a ready-to-mount upper that accepts standard Glock and Colt pattern magazines.

Key Features

• 6-inch nitride 4150 CrMoV barrel with 1:10 twist rate
• Billet aluminum upper receiver for pistol-caliber platforms
• Free-float quad-rail handguard with Picatinny mounting
• Aircraft-grade aluminum handguard with black finish
• Complete 9mm bolt carrier group with external extractor
• AR-15 M4 mil-spec charging handle included
• Witt Machine The Naughty 9 suppressor with graphite black Cerakote finish
• 1/2x28 thread pitch for suppressor mounting
• Glock and Colt pattern magazine compatibility

Perfect For

• Builders creating compact 9mm AR pistols
• Shooters wanting suppressed 9mm performance
• Users building pistol-caliber platforms with modular components
• Those seeking a complete upper assembly without lower receiver assembly

Complete Upper Assembly Configuration

This upper assembly includes the barrel, bolt carrier group, and charging handle. The 6-inch barrel length and 1:10 twist rate are optimized for standard 9mm ammunition. The free-float quad-rail design isolates the barrel from handguard pressure, supporting consistent shot placement. The billet upper receiver provides a solid foundation for the complete assembly.

Suppressor Integration and Performance

The Witt Machine The Naughty 9 is an ultra-compact 4-inch suppressor built from 416 stainless steel with graphite black Cerakote finish. It threads directly onto the 1/2x28 barrel, matching the platform standard. The compact design pairs with the 6-inch barrel to create a short overall package while maintaining sound reduction. Suppressor effectiveness depends on ammunition type, barrel length, and shooting environment.

Magazine and Compatibility Framework

This upper accepts both Glock and Colt pattern 9mm magazines, giving you flexibility in ammunition feeding. The external extractor design is standard for 9mm AR platforms. Compatibility with lower receivers requires verification of lower receiver design and magazine feed lips before assembly.

Nitride Barrel and Materials

The 4150 CrMoV steel barrel is finished in nitride, providing corrosion resistance and extended barrel life. The bolt carrier group uses 8620 alloy steel with nitride finish for durability. Aircraft-grade aluminum in the quad-rail handguard keeps overall weight minimal while maintaining rigidity under rail-mounted optics or accessories.

May Dropship from Davidson Defense.

Verify suppressor compatibility with your lower receiver before use.

Ensure secure mounting of the suppressor before operation.

Use only in accordance with all applicable federal, state, and local laws.

Follow safe handling and manufacturer instructions.

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