If a CWO is wearing the bursting bomb device, what are they referred to as?

A Chief Warrant Officer (CWO) wearing the bursting bomb device is referred to as a "Gunner." This designation is an important part of the Marine Corps' ranks and is specifically associated with CWOs who have demonstrated expertise in ordnance and munitions. The bursting bomb device symbolizes this proficiency in artillery and is a distinguishing mark that signifies the CWO's special skills and responsibilities.

The title "Gunner" not only reflects their technical capabilities but also indicates their leadership role within the Marine Corps, especially in areas that require specialized knowledge about weapons. This unique identification sets them apart from officers of higher ranks, such as Major, Colonel, and Captain, which do not carry the same connotations of specialized technical mastery in ordnance as the title of "Gunner" does. Thus, the correct association of the bursting bomb device with the term "Gunner" highlights the status and technical focus of the CWO within the Marine Corps.