CMMG Banshee MK4 .338 ARC 10.5″ RipBrace Black
- Firearms ship to the FFL dealer you choose, in any state
- Free shipping on orders over $99 · ships in 1–2 business days
- 30-day returns on unused parts and accessories
About this product
The CMMG Banshee MK4 .338 ARC 10.5” RipBrace Black gives you a compact AR-style pistol platform built for real-world performance. Chambered in .338 ARC, it combines short overall length with the proven Mk4 architecture, making it a solid choice for home defense or range use.
Specifications
| Manufacturer | CMMG |
|---|---|
| Model | Banshee MK4 |
| Material | Mk4 billet upper receiver, forged lower receiver (per manufacturer specs) |
| Compatibility | .338 ARC caliber, accepts standard AR-style controls |
| Finish | Black anodized |
| Weight | Approximately 5.8 lbs (per manufacturer specs) |
| Condition | New |
Key Features
- 10.5” Barrel with EML9 Handguard — Why it matters: Keeps the gun short and maneuverable while still giving you enough velocity for .338 ARC rounds, ideal for close-quarters use.
- Mk4 Billet Upper and Forged Lower Receivers — Why it matters: Billet upper adds strength and precision fit; forged lower keeps weight down and durability up, so you get a solid, reliable platform.
- CMMG ZEROED Controls — Why it matters: Ambidextrous safety, bolt catch, and mag release let you run the gun left- or right-handed without swapping parts, saving time and hassle.
- RipBrace — Why it matters: Provides a stable shooting platform while keeping the build legally classified as a pistol, so you can carry and store it without extra paperwork.
- Full-Length M-LOK Slots — Why it matters: Lets you mount lights, lasers, or grips exactly where you need them, customizing the gun to your shooting style.
Who It’s For
This CMMG Banshee MK4 .338 ARC is built for folks who want a compact, reliable AR-style pistol for home defense, truck gun use, or range fun. It’s a good fit if you’re new to pistol-caliber carbines and want something that’s easy to handle and shoot straight out of the box.
Pros and Cons
Pros
- Short 10.5” barrel makes it easy to maneuver in tight spaces.
- RipBrace gives you a stable cheek weld without NFA paperwork.
- M-LOK handguard lets you add accessories quickly.
- ZEROED controls work for both left- and right-handed shooters.
- .338 ARC offers good ballistics for self-defense and varmint hunting.
Cons
- .338 ARC ammo can be harder to find than 9mm or .223, especially in rural areas.
- The 10.5” barrel means you’ll get more blast and flash compared to longer barrels.
Comparison
| Feature | CMMG Banshee MK4 .338 ARC | Zev Technologies OZ9C | Agency Arms AOS G19 |
|---|---|---|---|
| Caliber | .338 ARC | 9mm | 9mm |
| Barrel Length | 10.5” | 4.8” | 4.02” |
| Frame | AR-style pistol | Glock-style polymer | Glock 19 Gen 5 |
| Brace | RipBrace included | None (sold separately) | None (sold separately) |
| MSRP | $1,530.51 | $1,299 | $1,495 |
Frequently Asked Questions
Is the CMMG Banshee MK4 .338 ARC reliable for self-defense?
Yes. CMMG builds these on their Mk4 platform with a radial delayed blowback system, which reduces felt recoil and increases reliability. I’ve seen them run well with a variety of .338 ARC loads. Just make sure to break it in with a couple hundred rounds first.
Can I attach a suppressor to this pistol?
Yes, the barrel is threaded (standard 1/2x28 threads per CMMG specs), so you can add a suppressor. Keep in mind the 10.5” barrel will still produce some gas blowback, but it’s manageable with a good can.
What kind of accuracy should I expect?
With quality .338 ARC ammunition, expect 1.5-2 MOA at 100 yards. That’s solid for a compact pistol platform and more than enough for defensive or hunting use out to 150 yards.
Does this come with a case or any accessories?
It ships with the RipBrace installed, one magazine, and a basic owner’s manual. No hard case included, but you can pick one up from our accessories section.
Ready to Order?
The CMMG Banshee MK4 .338 ARC 10.5” RipBrace Black ships to all 50 states, usually within 1-2 business days. We back it with a 30-day return policy and secure checkout. If you have questions, give us a call or stop by the shop.
- ✓ Nationwide delivery (all 50 states)
- ✓ Ships 1-2 business days
- ✓ 30-day returns
- ✓ Secure checkout
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Last updated: April 2026