The ZK 412, or the MK SS-42, is an experimental Czech assault rifle.
History[]
The rifle was designed by Koucký brothers, as evidenced by the "ZK" naming. The first prototypes were finished in either 1941 or 1942. The weapon was apparently trialed and even captured on the eastern front where it was tested, but that is unconfirmed.
Design Details[]
The weapon used a top-mounted fixed gas piston with nested recoil spring and under-hanging bolt carrier with a rotary bolt, which would later be seen in the AK series of rifles.
Ammunition[]
A diagram of the bullet.
The weapon fired the 8mm Rapid bullet, a round-nosed 8 gram bullet.