Missouri-based CMMG on Tuesday announced the first firearm made for the American consumer market chambered in 4.6×30– the FourSix.
Designed originally by Heckler & Koch in the 1990s for a low-recoiling NATO Personal Defense Weapon program– competing against FN’s 5.7×28 for the same purpose– the 4.6x30mm is a rimless bottlenecked cartridge that performs well under 150 yards whose small size allows guns chambered for it to carry a lot of rounds.
Fast forward 20+ years and, while both cartridges have been adopted by NATO and standardized, only the 5.7×28 has been utilized by other firearms makers (e.g., Ruger 57, Diamondback DBX57) outside of its original designer. In short, the 4.6 NATO has only been used by the select-fire (and very Post-1986) HK MP7, putting it off-limits for those without a SOT or a CAC card.
Tweaks to the Banshee needed to run the 4.6 include a patent-pending Micro Gas Block and a proprietary 40-round magazine that fits an AR-style magwell and standard mag pouches. The latter part is key as it means users can also choose to pair their existing AR15 lower receiver with a CMMG FourSix upper, when they become available.