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CMMG Banshee 10mm Review

Pistol caliber carbines (PCCs) are popular, and after spending time at the range with the new CMMG Banshee 10mm, it's easy to understand why there's so much interest in these firearms.

CMMG Banshee 10mm Review
The CMMG Banshee is a superb PCC that’s fiendishly fun to shoot.

Photos courtesy of Brad Fitzpatrick.

CMMG has reinvented the pistol caliber carbine market with the introduction of their new Banshee line of AR pistols, and the new 10mm Auto version offers fans of that caliber a high-tech, reliable, and smooth-shooting 10mm PCC with a refined operating system and all the high-end features you’d expect from a CMMG firearm. For fun at the range, hunting, or personal defense it’s impossible to beat all that the Banshee 10mm offers.

The new CMMG Banshee 10mm measures just 24.3 inches long and comes with an adjustable arm brace, 8-inch barrel, and, where legal, a 30-round 10mm magazine (it’s also compatible with Glock 10mm mags as well). Weighing in at just 5 pounds, 9 ounces, unloaded, the Banshee is light, yet it produces mild recoil, making it a fun and versatile PCC that’s ideal for personal defense, hog or deer hunting, or hammering steel and paper targets at the range.

CMMG Banshee 10mm

At the heart of the Banshee 10mm is CMMG’s groundbreaking Radial Delayed Blowback action. Unlike traditional straight blowback designs, the Radial Delayed Blowback system incorporates a mechanical delay that forces the bolt to rotate, slowing the bolt carrier group so that chamber pressures to drop before cycling. This allows the Banshee to use a lighter bolt, buffer, and spring than competing PCCs, and the reduced bolt velocity reduces wear and recoil. The system also functions with a wide array of 10mm loads, and since more gas is vented down the barrel the Banshee functions cleaner than other PCCs—a major advantage when shooting suppressed.

“From the moment we first introduced the Radial Delayed Blowback operating system back in 2017, our customers have repeatedly requested that we use this innovative system to chamber 10mm,” says Chris Reinkemeyer, CEO/CFO at CMMG. “We are proud to say that we have now answered the call. Not only do our 10mm offerings work with the wide range of ammunition available today, they also tame the felt recoil by significant a margin.”

CMMG Banshee 10mm

There’s substantial variation among factory 10mm loads with regard to energies, bullet weights, pressures, and muzzle velocities, and CMMG designed the Banshee so shooters could take full advantage of the wide array of 10mm ammo available today. The gun ships with a five-ounce H3 buffer installed. The H3 buffer functions with a wide range of 10mm loads, but there’s also a three-ounce standard carbine buffer included in the box that is tuned for maximum performance from light ammunition. For those who prefer to run max power ammo there’s also an available eight-ounce buffer available from CMMG as well. This means you can tune your Banshee to function with any 10mm load you’d like with or without a suppressor, making this one of the most versatile 10mm PCCs available.

One of the gripes shooters levy against PCCs is that the bolt doesn’t lock open after the last round is fired, slowing the reloading process. The engineering team at CMMG set out to find a solution to this problem, and this led to the development of the company’s patented Bolt Catch Linkage System. The dual-pinned and precision-machined Bolt Catch Linkage System allows for bolt hold-open following the last round, and the system has been thoroughly tested and has proven reliable. The reloading operation for the Banshee is similar to AR-15 platform rifles, and it’s significantly faster than PCCs without the Bolt Catch Linkage System feature.

Why the 10mm?

The 10mm Auto is enjoying a resurgence in popularity. Developed by Colonel Jeff Cooper in 1983, the 10mm Auto offered substantial stopping power but the recoil proved to be too much for some shooters. Today, however, the 10mm is being recognized for its ability to balance threat-stopping energy and maximum magazine capacity, making it an ideal defensive round against two and four-legged attackers. The CMMG Banshee makes the potent 10mm Auto even more versatile by chambering it in a smooth-running, easy-carrying PCC. Adding to its appeal to 10mm fans is the Banshee’s ability to run with the supplied 30-round magazines or Glock mags without modification.

CMMG Banshee 10mm

CMMG offers three different series of their Banshee pistols and SBR firearms (100, 200, and 300 series) in calibers ranging from .22 LR to .458 SOCOM. CMMG Banshee 100 Series pistols are basic but well-appointed and offer an affordable entry into the 10mm PCC market with MSRPs of $1,299.95 for the pistol and $1,349.95 for the SBR. The upgraded 200 Series pistols and SBRs offer upgrades like enhanced arm braces, and the line-topping 300 Series guns come with ambidextrous safety selectors and are available in a variety of Cerakote color options. CMMG Banshee 200 Series 10mm pistols and SBRs carry and MSRP of $1,449.95 while the 300 series guns have an MSRP of $1,649.95. All Banshee pistols come equipped with 7075 T-6 receivers, M-LOK free float handguards, and SBN barrel finishes, and all are backed by CMMG’s lifetime warranty.

CMMG Banshee On the Range

The CMMG Banshee 10mm 300 Series pistol I tested came equipped with CMMG Micro/CQB RipBrace five-position arm brace with QD attachment point and Ambi Sling Plate, a CMMG Ambi safety selector, CMMG RML7 M-Lok Handguard, CMMG Oversized Ambi charging handle and the company’s single-stage mil-spec style trigger. It also featured a Cerakote Titanium finish on the handguard and receiver. I mounted a Leupold Freedom RDS 1x34 red dot optic on the Banshee and the combination proved to be very accurate. From 25 yards five-shot sub-inch groups were possible, and the Banshee ran smoothly with a wide range of ammo from Federal, Speer, Hornady, and Sig with the H3 buffer in place, so many shooters won’t find it necessary to switch buffers. However, having the option to do so and run very light or very heavy loads adds to the Banshee’s versatility. What’s more, the Banshee’s added barrel length gleans the most velocity and energy from defensive loads. Speer’s 200-grain Gold Dot HP ammo, which is rated for at 1,100 fps, averaged 1,142 fps measured ten feet from the muzzle. The other loads in the test saw similar upticks in velocity.

CMMG Banshee 10mm

The 10mm Auto cartridge has a reputation for producing potent recoil, but the Banshee’s Radial Delayed Blowback action did a good job of keeping the gun settled. There’s very little muzzle rise and minimal setback. Even the most recoil-sensitive shooter can run this pistol without any issues, and it’s possible to deliver fast, accurate follow-up shots. The Bolt Catch Linkage never failed to keep the action open following the last shot which makes reloading faster and easier.

CMMG Banshee 10mm

For LE professionals looking for a compact weapon with ample stopping power and a prodigious magazine capacity the Banshee is a natural choice, and it’s also a great option for home defense. Hunters will also love the versatility, power, and capacity the Banshee offers, and it’s a blast to take to the range because it’s accurate, reliable, and offers minimal recoil. The Banshee is available in a number of calibers, but 10mm fans won’t want to miss out on the Mk10. It’s a superb PCC that’s fiendishly fun to shoot.


CMMG Banshee Series 300 Mk10 Specifications

  • Caliber: 10mm Auto
  • Action: CMMG Radial-Delayed Blowback
  • Capacity: 30 round SGM Tactical (1 mag provided—also functions with Glock 10mm Auto magazines)
  • Collapsed Length: 24.3 inches
  • Weight: 5 pounds, 9 ounces
  • Trigger: CMMG Single Stage Mil-Spec
  • Pistol Brace: CMMG Micro/CQB RipBrace w/5-Position Enhanced receiver Extension
  • Receiver: Forged 7075-T6 AL Upper and Lower
  • Finish: Titanium Cerakote Receiver/Handguard, SBN Barrel
  • Hand Guard: CMMG RML7 M-Lok Hand Guard
  • Barrel: 8 inches, CMMG SV Muzzle Brake Compensator
  • Extras: One SGM Tactical Magazine, Ambi Sling Plate, CMMG Oversized Charging Handle, Magpul MOE Pistol Grip, Manual
  • MSRP: $1,649.95 (as tested)
  • Contact: CMMG Incorporated (660) 248-2293
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