CMMG’s New MK57 Banshee 5.7x28mm Pistol and SBRs
The 5.7 x 28 is a bit of an odd round. Developed for use in the PDW P90 platform and FN 5.7 pistol the round is moderately famous for such an oddball. Over time the round has gained a bit more steam, and FN seems to be happy to let others build on their round. From ARs uppers that take P90 magazines to Excel arms pistols, the cartridge is slowly finding it’s way into other guns. The newest being the new line of AR pistols and SBRs from CMMG. While these aren’t the first ARs in 5.7, they are the first I know of that use the FN pistol magazine versus the P90 magazine. These MK57’s are an attractive design.
CMMG likes to push the boundaries of the AR platform and is doing so with this idea. Instead of a traditional blowback design, they are incorporating a radial delayed blowback system. This is going to increase reliability, as well as keep the system low recoiling and safer overall. The 5.7 round is an oddball. It’s not exactly a pistol round and not exactly a rifle round, but seems to work well in short barreled guns in general. The CMMG MK57 series will include options for both 8-inch barrels and 5-inch barrels. The weapons will be known as the PSB and Banshee respectively.
The Banshee will come as an SBR or a pistol, and the SBR variant will come with a Magpul vertical grip and CMMG’s new RipStock. The pistols variants will come with the always excellent Gear Head Works Tailhook Mod 2. This brace adjusts on a four position AR buffer tube. The Banshee will have a short M-LOK rail and come in 11 different colors.
The PSB model will have an 8-inch barrel and be a pistol only. It will ship with a KAK brace, M-LOK rail. The PSB model is a little cheaper and will make excellent use of the 5.7’s ballistics through its 8-inch barrel.
Since the guns use a standard layout instead of a top loaded P90 magazine, most AR owners will be familiar with the controls and handling of the weapon. Reloads will be a bit more intuitive, and the FN 5.7 has plenty of high cap magazine available. CMMG even makes a plus 10 round extender for 5.7 mags, so there is that.
Both guns will have appropriately sized magwells, this isn’t some kind of shove a mag block adapter, but purpose built weapons. Each weapon will come with a 20 round Promag magazine, which is the biggest downside to me. They accept standard FN 5.7 magazines and I think should include them. At the price point, these guns are selling at I would expect OEM magazines, not aftermarket options from a company not known for greatness. I’m hoping this choice was to do more to logistics than cost-cutting measures. It may be hard to get ahold of FN 5.7 mags to complete the builds.
The MK57 SBRs and pistols indeed seem to be a viable alternative to the 9mm carbine feeding from a Glock magazine. The 5.7 round will offer a little more range, penetrative ability, and quite possibly a safer round to use indoors for home defense. I’ve never seen drywall tests, but if it performs anything like 5.56, it’s less likely to overpenetrate and keep going and going if a miss occurs.
I like the 5.7 round I keep hoping it gets a bit more popular and CMMG is undoubtedly trying to answer my prayers. Keep an eye for these new guns as they should hit retailers soon.
The post CMMG’s New MK57 Banshee 5.7x28mm Pistol and SBRs appeared first on Omaha Outdoors.