It seems rare these days that we have a bit of good news in the firearms world. Even when it’s good news, it’s usually a silly compromise. The latest example is the removal of the $200 tax stamp cost for certain NFA items. We kept the NFA paperwork and the registry, but hopefully, by removing the tax, we can now nuke the legislation entirely. The change has caused a massive surge in NFA items being registered, and I joined the trend by obtaining my first short-barreled rifle, a 9mm CMMG Banshee.
Why The Banshee SBR?
The irony of registering a pistol caliber carbine as my first short-barreled rifle isn’t lost on me. However, I have always loved subguns. Super short, light little firearms with minimal recoil are my jam. You can get some incredibly compact rifles chambered in rifle calibers, but the 9mm cartridge appeals to me for a number of reasons.
Nine millimeter parabellum is easy to find, easy to suppress, and it’s not exactly going to be a concussive experience firing from a 5-inch barrel. I know 300 Blackout is better in almost every way, but wake me up when 300 Blackout drops below 20 cents a round. For shooting targets made of steel and cardboard, 9mm is a much more appealing choice.
I went with the Banshee because I figured if I was getting an SBR, I might as well get a premium model. The 1911 of the subgun world, the MP5 just doesn’t appeal to me. I wanted better ergonomics, cheaper accessories, and a much easier way to mount optics. Plus, I’m fond of last round bolt hold-open.
Going Radial Delayed
The Banshee uses a radial delayed mechanism. This system utilizes a bolt that looks awfully similar to a standard AR-15 bolt, but you’ll notice the locking lugs are slightly rounded. Those lugs lock into the CMMG barrel extension and when the gun fires, they have to rotate out of the extension to allow the bolt to move rearward and cycle the weapon.
It’s important to note that this isn’t a true locking system, but rather a delaying system. With a standard straight blowback gun, the only thing keeping the action closed as the projectile leaves the barrel is the physical weight of the bolt and buffer setup.
That design creates a heftier gun that tends to have a fair bit of recoil for a 9mm. Most AR-9s typically feel like a 5.56 rifle, which isn’t a lot of recoil in a vacuum, but it is more than you want from a pistol round. Radial delayed guns are lighter and have very soft recoil.
My CMMG Banshee
My Banshee is the Mk17 model which uses SIG SAUER P320 magazines. The gun has been outfitted with a SilencerCo Spectre 9, a Surefire Mini Scout Light Pro, a vertical foregrip, and a Holosun AEMS enclosed in an ANVL UKON mount.
As a package, it’s a pretty decent home defense gun. Admittedly, it’s still just a pistol caliber, but it’s an ultra-lightweight, easy-to-control weapon. I’m a shotgun man when it comes to defensive firearms, but for a smaller-statured or recoil-sensitive shooter, this setup is awesome.
This configuration has its quirks, to be sure. The vertical grip is just there because I flat-out like it. However, a vertical grip on an ultra-short rail means my thumb has to come off the grip to hit the light’s rear clicky button. I have a pressure switch planned in the near future to solve that issue.
The Surefire Mini is great for this super-small gun. I’m not taking long-range shots with this platform, and it offers more than enough light to fill a living room. The Holosun AEMS is a great red dot and the ANVL UKON mount puts it at the perfect height for comfortable use while providing built-in backup iron sights.
Pair the gun with a 21-round magazine and you have an excellent bag gun. The 21-rounder doesn’t extend past the pistol grip, keeping things incredibly compact. Of course, 32-rounders are available when you want a bit more ammo on board.
The suppressor saves your ears, reduces muzzle flash, and makes the gun shoot even softer. The SilencerCo Spectre 9 weighs less than four ounces, so the gun remains very lightweight. Banshees are supposed to howl, but I wanted this one to keep it down as much as possible.
At the Range With the Banshee SBR
I adore this gun. It’s probably my favorite PCC. It’s not my only radial delayed gun, but it’s my only SBR. I shoot the absolute hell out of it, so we will get the bad news out of the way up front. The ejector spring on these older spring-loaded bolt-face models wears out quickly, leading to failures to eject. To remedy this, I replaced mine with the heavier MK10 ejector spring, which is supposed to last at least a thousand rounds.
The MK10 ejector spring is only $1.50, but shipping costs about six bucks, so I ordered ten of them to keep the gun running for a good bit. The part is cheap, but this gun is expensive and I really shouldn’t have to change the ejector spring every thousand rounds or so. I’ve already committed to the SBR build, so I’m ready to address the problem.
CMMG now offers a fixed ejector kit, which comes standard on their newer fixed ejector Banshee FE and Dissent lines. I can retrofit mine, but that requires spending another $425 for a new upper and bolt carrier group. I don’t want to deal with that expense right now. For $22, I have enough ejector springs to last a good 10,000 rounds.
Beyond The Bad News
Beyond the ejector spring issue, the gun runs reliably. Suppressed or unsuppressed, it runs great. The radial delayed design can even be tuned with an Action Tuning Kit, a series of weights attached to the carrier via a roll pin.
If you are using hot ammo and a suppressor, the tuning kit can help slow the bolt down to reduce recoil and prevent the moving parts from beating themselves to death. For standard 115-grain FMJs, I have never seen the need to add the extra weight, but I keep it in my kit just in case.
The recoil is incredibly light and a gun this short is a total blast to shoot. You can drive rounds as fast as you want and the muzzle doesn’t buck or rise much at all. Hitting sub-second Bill Drills with it will never get old.
The radial delayed system combined with a suppressor makes this gun incredibly pleasant to shoot. It’s downright cozy. The super-short profile makes it easy to transition between targets and to move dynamically, even in tight spaces. If I had to clear a house, I would feel pretty good doing it with the CMMG Banshee SBR.
Ringing Steel
Hitting shots out to about a hundred yards isn’t off the table. With the red dot mounted, I can regularly engage a 10-inch gong from a rested position at 100 yards. It takes a bit of a holdover because I zeroed the dot at 25 yards, and 9mm has a bit of a rainbow trajectory at triple digits.
Inside 100 yards, it’s exceptionally accurate. We’re talking about holes touching at 25 yards from a rested position using the cheapest Monarch steel-case ammo I can find.
At 50 yards, I’m easily killing reduced-size IPSC targets and the smallest 6-inch gong I own. Keeping the steel ringing is a smile-inducing experience.
The ergonomics are fantastic across the board. The safety is ambidextrous and tactile. The charging handle is massive and also ambi. Because the gun features last-round bolt hold open, reloads are fast and intuitive. The magazine release is easy to reach with your trigger finger and the P320 magazines drop completely free.
Bottom Line
That ejector spring thing is a pain. It’s a design flaw that shouldn’t have been overlooked and slightly stains what is otherwise a fantastic gun. I’m glad CMMG transitioned to a fixed ejector on their newer uppers, meaning the problem no longer exists for current buyers.
Other than that minor maintenance headache, this is by far one of my favorite firearms. I love the Banshee. It is incredibly fun to shoot and easy to suppress without getting a face full of blowback gas. It’s short, light, accurate, and low-recoiling, fulfilling everything I want from a subgun. The only thing that could make it better is if the NFA didn’t exist at all, allowing me to flip that safety selector to a third position.