CMMG Banshee 300 MK4 RDB 9mm Pistol for Sale – The Ultimate AR-9mm Evolution

At Weapons Ammo Reloaded, we proudly present the CMMG Banshee 300 MK4 RDB 9mm Pistol for sale—a next-generation AR-pistol that redefines performance in the pistol-caliber carbine category. Engineered with CMMG’s patented Radial Delayed Blowback (RDB) system, the Banshee 300 MK4 delivers rifle-like reliability with significantly reduced recoil, making it the ultimate choice for home defense, competition, and tactical applications.

Unrivaled Performance Features

• Radial Delayed Blowback System – Smoother operation than direct blowback, with 40% less recoil and no bolt bounce
• 8″ Barrel – 1:10 twist rate, optimized for 9mm +P and suppressor use (threaded 1/2×28)
• MK4 M-LOK Handguard – Free-floated, lightweight, and fully customizable for lights, grips, and lasers
• Ambidextrous Controls – Includes bolt release, safety selector, and magazine release
• EndoMag™ Compatibility – Uses 9mm-converted AR-15 mags (or Glock mags with optional lower)
• SB Tactical SBA3 Brace – Adjustable for stability while maintaining pistol classification

Specifications

• Caliber: 9mm Luger (handles +P)

• Barrel Length: 8″ (threaded 1/2×28)

• Overall Length: 22.5″ (collapsed) / 25.75″ (extended)

• Weight: 5.2 lbs (unloaded)

• Magazine Capacity: 30+1 (included, EndoMag insert)

• Receiver: Forged 7075-T6 aluminum (Type III hardcoat)

• Trigger: Single-stage mil-spec (3.5-4.5 lb pull)

Why the Banshee 300 MK4 RDB?

• Superior Reliability – No more feeding issues common in direct blowback PCCs

• Competition-Ready – Dominates USPSA PCC and Steel Challenge matches

• Suppressor-Friendly – Reduced gas blowback for cleaner suppressed shooting

• AR-15 Platform Familiarity – Same controls, ergonomics, and modularity

Perfect For

• Home Defense – Compact size with rifle-level control

• Tactical Use – Ideal for CQB and vehicle operations

• Competition Shooting – Low recoil for faster follow-up shots

• Suppressed Shooting – Exceptionally quiet with subsonic ammo

Included

• (1) 30-round EndoMag (PMAG body)

• SB Tactical SBA3 brace

• Thread protector

The CMMG Banshee 300 MK4 RDB 9mm Pistol is the pinnacle of AR-9mm innovation—available now at Weapons Ammo Reloaded.