Haenel MK 556

The Haenel MK 556 is a gas-operated, selective-fire 5.56x45mm NATO assault rifle developed for military use by the German company C.G. Haenel, finalized in September 2020 after building on an earlier semi-automatic civilian variant, the CR 223, that had seen limited law enforcement use since 2017. It uses a short-stroke gas piston operating system rather than the direct impingement design common to AR-15 pattern rifles, with a user-adjustable gas regulator, over-the-beach tested reliability after water exposure, a cold hammer-forged barrel with a standard A2-style flash suppressor, a rate of fire of about 900 rounds per minute, and compatibility with standard 30-round STANAG magazines or 100-round Beta C-Mag drums. The rifle is built with modular construction compatible with AR-15, M16, and M4 accessories, and it was initially selected to replace Germany's aging G36 rifle before that procurement decision ran into legal complications.