The US Navy has ordered 55 Mark 38 Mod 4 anti-drone guns, a 30mm cannon that can fire air burst rounds, but USS Mustin is still the only destroyer known to carry it. Here's how the new gun works, why the Navy is buying it now, and which ships get it next.
The Mk 38 Mod 4 stacks a 30mm Bushmaster II chain gun and a .50 caliber machine gun on one remote-controlled mount. It is the first caliber increase for the Mark 38 family in more than 30 years. Its air burst rounds explode right next to a drone, so the gun no longer needs a direct hit, and it is built to work with the Aegis combat system, linking radar, cameras and gun.
USS Mustin (DDG-89), an Arleigh Burke class destroyer forward-deployed to Yokosuka, Japan, received the first Mod 4 in 2024. In 2026 she fired it in live-fire training in the South China Sea and the Indian Ocean. Under a new contract signed on September 30, 2026, the Navy plans to fit the gun on every Flight IIA and Flight III destroyer, and on the Coast Guard's new heavy polar icebreakers.
Source: The Navy Channel
