Infantry weapons officer

U.S. Marine Corps Gunner insignia

The United States Marine Corps MOS 0306, infantry weapons officers, commonly referred to as "the Gunner" or "Marine gunner" are non-technical chief warrant officers (CWO-2 to CWO-5) that are weapons specialists and are knowledgeable in the tactical employment of all the infantry weapons in the Marine Corps arsenal—all weapons organic to Marine infantry units.