A gunnery sergeant is a senior rank in the United States Marine Corps, positioned above staff sergeant and below master sergeant. Gunnery sergeants, often called “Gunny” for short, serve as technical experts and experienced leaders who train and guide younger Marines.

The rank originated in the 1800s when these sergeants specialized in operating artillery and naval guns, but today they lead Marines in all kinds of roles: infantry, logistics, communications, and more. A gunnery sergeant typically has at least 10 years of service and has proven themselves as both skilled Marines and effective teachers.

In Marine Corps culture, gunnery sergeants hold a special place. They're the ones who know every detail of their job and can solve problems that baffle less experienced Marines. When a captain needs to know if a mission plan will actually work in the field, they often ask their gunny. When new privates need to learn their jobs properly, a gunnery sergeant teaches them what to do and why it matters.

The rank insignia has three chevrons pointing up and two rockers underneath, with two crossed rifles in the center. If you've seen movies featuring tough, experienced Marine instructors who seem to know everything about military life, there's a good chance they were playing gunnery sergeants.