CMMG126821073
CMMG Banshee MK4 Pistol 300BLK 12.5" - Armor Black$1,444.17
Availability: In Stock
The CMMG BANSHEE MK4 Pistol in .300 BLK with an 8-inch barrel delivers serious capability in a compact, maneuverable package. Built on the proven Mk4 platform, this .300 BLK AR pistol excels in close-quarters applications, home defense, and suppressed shooting—especially with subsonic ammunition. The 1:7 twist barrel stabilizes a wide range of .300 BLK loadings, from whisper-quiet subsonic rounds to supersonic hunting ammo that rivals intermediate cartridges like 7.62x39. At just 5.1 lbs and 23.7 inches overall, it's purpose-built for rapid target acquisition and tactical mobility without sacrificing the ergonomics and modularity that make AR-platform guns so adaptable.
Every major component is engineered for durability and user control. The billet 6061-T6 aluminum upper pairs with a Mk4 forged 7075-T6 lower receiver for a rigid, reliable foundation. The direct-impingement system pairs a pistol-length gas port with a non-adjustable 0.750 gas block, tuned for the platform's performance envelope. CMMG's ZEROED line handles the controls: an ambi charging handle, drop-in single-stage trigger, 60/90-degree safety, and ergonomic pistol grip designed for intuitive operation in any firing position. The CMMG RipBrace provides a modern, quick-deploying solution for legal compliance and support.
The EML7 M-LOK handguard gives you abundant mounting real estate—full-length slots on both sides, the bottom, and between top Picatinny sections—so you can outfit it exactly as you need it. The CMMG ZEROED linear compensator (5/8x24 thread) manages muzzle signature and recoil impulse. A 30-round Magpul PMAG feeds reliably, and the carbine buffer system is tuned for this short-barrel platform. Finished in armor-black Cerakote, it's a no-nonsense tool ready for duty or the range.
| Caliber | .300 BLK |
| Platform | CMMG Mk4 |
| Barrel Length | 8 inches |
| Barrel Material | 4140CM SBN steel |
| Barrel Twist | 1:7 |
| Barrel Contour | MT |
| Operating System | Direct impingement |
| Gas Port | Pistol length |
| Gas Block | 0.750-inch non-adjustable |
| Muzzle Device | CMMG ZEROED linear compensator |
| Muzzle Thread | 5/8x24 |
| Upper Receiver | Billet 6061-T6 aluminum |
| Lower Receiver | Mk4 forged 7075-T6 aluminum |
| Handguard | CMMG EML7 M-LOK |
| Receiver Extension | CMMG 6-position Fastback |
| Stock / Brace | CMMG RipBrace |
| Charging Handle | CMMG ZEROED ambi |
| Trigger | CMMG ZEROED drop-in single stage |
| Trigger Guard | CMMG ZEROED |
| Safety Selector | CMMG ZEROED 60/90 degree |
| Pistol Grip | CMMG ZEROED |
| Buffer Type | Carbine |
| Magazine | 30-round Magpul PMAG |
| Finish | Cerakote (armor black) |
| Weight | 5.1 lbs |
| Overall Length | 23.7 inches |
The BANSHEE MK4 is purpose-built for close-quarters applications, home defense, and suppressed shooting. The 8-inch barrel and direct-impingement system are optimized for .300 BLK subsonic ammunition, making it ideal for quiet, suppressed use. It also handles supersonic .300 BLK loads that compete with intermediate cartridges like 7.62x39, so it's versatile enough for hunting and range work where noise isn't a constraint.
Yes. .300 BLK was originally designed for short-barrel applications and performs exceptionally well with subsonic suppressed loads. With supersonic ammunition, it has evolved into a capable hunting cartridge that rivals other intermediate rounds. The 1:7 twist barrel in this pistol stabilizes a wide range of .300 BLK loadings, so you can choose subsonic for stealth or supersonic for hunting performance depending on your application.
The BANSHEE MK4 ships with a 30-round Magpul PMAG. All the controls and components—the CMMG ZEROED trigger, charging handle, safety, grip, brace, and linear compensator—are installed and ready to use.
Absolutely. The CMMG ZEROED linear compensator is threaded 5/8x24, so you can attach a suppressor or other muzzle devices. The EML7 M-LOK handguard has full-length M-LOK slots on both sides, the bottom, and between the top Picatinny rail sections, giving you extensive real estate to mount lights, lasers, grips, and other must-have gear exactly how you want it.
SKU: 126824231 • Weight: 6.84oz
Availability: In Stock
The CMMG BANSHEE MK4 Pistol in .300 BLK with an 8-inch barrel delivers serious capability in a compact, maneuverable package. Built on the proven Mk4 platform, this .300 BLK AR pistol excels in close-quarters applications, home defense, and suppressed shooting—especially with subsonic ammunition. The 1:7 twist barrel stabilizes a wide range of .300 BLK loadings, from whisper-quiet subsonic rounds to supersonic hunting ammo that rivals intermediate cartridges like 7.62x39. At just 5.1 lbs and 23.7 inches overall, it's purpose-built for rapid target acquisition and tactical mobility without sacrificing the ergonomics and modularity that make AR-platform guns so adaptable.
Every major component is engineered for durability and user control. The billet 6061-T6 aluminum upper pairs with a Mk4 forged 7075-T6 lower receiver for a rigid, reliable foundation. The direct-impingement system pairs a pistol-length gas port with a non-adjustable 0.750 gas block, tuned for the platform's performance envelope. CMMG's ZEROED line handles the controls: an ambi charging handle, drop-in single-stage trigger, 60/90-degree safety, and ergonomic pistol grip designed for intuitive operation in any firing position. The CMMG RipBrace provides a modern, quick-deploying solution for legal compliance and support.
The EML7 M-LOK handguard gives you abundant mounting real estate—full-length slots on both sides, the bottom, and between top Picatinny sections—so you can outfit it exactly as you need it. The CMMG ZEROED linear compensator (5/8x24 thread) manages muzzle signature and recoil impulse. A 30-round Magpul PMAG feeds reliably, and the carbine buffer system is tuned for this short-barrel platform. Finished in armor-black Cerakote, it's a no-nonsense tool ready for duty or the range.
| Caliber | .300 BLK |
| Platform | CMMG Mk4 |
| Barrel Length | 8 inches |
| Barrel Material | 4140CM SBN steel |
| Barrel Twist | 1:7 |
| Barrel Contour | MT |
| Operating System | Direct impingement |
| Gas Port | Pistol length |
| Gas Block | 0.750-inch non-adjustable |
| Muzzle Device | CMMG ZEROED linear compensator |
| Muzzle Thread | 5/8x24 |
| Upper Receiver | Billet 6061-T6 aluminum |
| Lower Receiver | Mk4 forged 7075-T6 aluminum |
| Handguard | CMMG EML7 M-LOK |
| Receiver Extension | CMMG 6-position Fastback |
| Stock / Brace | CMMG RipBrace |
| Charging Handle | CMMG ZEROED ambi |
| Trigger | CMMG ZEROED drop-in single stage |
| Trigger Guard | CMMG ZEROED |
| Safety Selector | CMMG ZEROED 60/90 degree |
| Pistol Grip | CMMG ZEROED |
| Buffer Type | Carbine |
| Magazine | 30-round Magpul PMAG |
| Finish | Cerakote (armor black) |
| Weight | 5.1 lbs |
| Overall Length | 23.7 inches |
The BANSHEE MK4 is purpose-built for close-quarters applications, home defense, and suppressed shooting. The 8-inch barrel and direct-impingement system are optimized for .300 BLK subsonic ammunition, making it ideal for quiet, suppressed use. It also handles supersonic .300 BLK loads that compete with intermediate cartridges like 7.62x39, so it's versatile enough for hunting and range work where noise isn't a constraint.
Yes. .300 BLK was originally designed for short-barrel applications and performs exceptionally well with subsonic suppressed loads. With supersonic ammunition, it has evolved into a capable hunting cartridge that rivals other intermediate rounds. The 1:7 twist barrel in this pistol stabilizes a wide range of .300 BLK loadings, so you can choose subsonic for stealth or supersonic for hunting performance depending on your application.
The BANSHEE MK4 ships with a 30-round Magpul PMAG. All the controls and components—the CMMG ZEROED trigger, charging handle, safety, grip, brace, and linear compensator—are installed and ready to use.
Absolutely. The CMMG ZEROED linear compensator is threaded 5/8x24, so you can attach a suppressor or other muzzle devices. The EML7 M-LOK handguard has full-length M-LOK slots on both sides, the bottom, and between the top Picatinny rail sections, giving you extensive real estate to mount lights, lasers, grips, and other must-have gear exactly how you want it.
SKU: 126824231 • Weight: 6.84oz