The M242 Bushmaster is a powerful 25x137mm cannon, originally manufactured by Hughes Ordnance in Culver City, California. It was later acquired by Boeing and fielded on everything from Naval ships to the LAV-25, a powerful light armored vehicle that mounts the bushmaster on a turret. The version seen in this video aboard the USS Kearsarge is the Mk38, a special naval version fielded specifically by the U.S. Navy to defend from patrol boats, surface mines, and even pirates.
As we see in the video, the Mk 38 MOD 2 has a much sleeker housing design than previous models, which protects it from weather and allows for easy access to internal components. The Bushmaster is also incredibly loud and, as demonstrated by both the shooter and spotter, hearing protection is a must while operating.
The cannon operates on a chain drive system and can be dual fed through a metallic linking system. The gun also features special optics that assist the gunner in making the most accurate shots possible, while allowing them to adjust the crosshairs, view the range, and switch between light and dark modes. The single barrel, air cooled cannon fires up to 175 rounds per minute, and its special fluted design allows for quick cooling.
Check out the video below to see it in action: