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 (CWO2 to CWO5) that are weapons specialists and are knowledgeable in the tactical employment of all the weaponry in Marine Corps arsenal—all weapons organic to the Marine infantry units.

Overview

The requirements to apply for selection are very stringent and much higher than what is needed for other warrant officer appointments. For example; minimum time in service is sixteen years and minimum rank to apply is Gunnery Sergeant (E-7) versus eight years and Sergeant (E-5). They are not appointed Warrant Officers, but rather commissioned directly to the grade of Chief Warrant Officer-2 and are the only officers who are officially designated the title, "Marine Gunner" and authorized to wear the "Bursting Bomb" insignia.

The title "Gunner" is almost always used in lieu of rank (i.e., "Gunner Smith" as opposed to "Chief Warrant Officer Smith"), and the rank insignia worn on the left collar is replaced with a "Bursting Bomb", a larger "Bursting Bomb" insignia is worn ¾" above the rank insignia on both shoulder epaulets when a coat is worn. Occasionally other warrant officers are referred to as "Gunner" but this is incorrect and typically done out of laziness or ignorance.

In the United States Armed Forces, the ranks of warrant officer (grades W-1 to W-5) (NATO: WO1-WO5) are rated as officers above the senior-most enlisted ranks, including all officer candidates (OC) and warrant officer candidates (WOC) (both of whom hold enlisted grades as E-5 or above, depending upon their grade upon appointment as an OC or WOC); and cadets and midshipmen (who are considered "officers only in a qualified sense", holding a special grade above E-9 and below W-1), but subordinate to the officer grade of O-1 (NATO: OF-1). This application differs from the Commonwealth of Nations and other militaries, where warrant officers are the most senior of the other ranks (NATO: OR-8 and OR-9), equivalent to the US Armed Forces grades of E-8 and E-9.

Warrant officers are highly skilled, single-track specialty officers, and while the ranks are authorized by Congress, each branch of the uniformed services selects, manages, and utilizes warrant officers in slightly different ways. For appointment to warrant officer one (W-1), a warrant is approved by the secretary of the respective service. For chief warrant officer ranks (W-2 to W-5), warrant officers are commissioned by the President of the United States and take the same oath as regular commissioned officers (O-1 to O-10).