Infantry Weapons Officer 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 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 vice eight , and minimum rank to apply is Gunnery Sergeant ( E - 7 ) vice 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 3 / 4 " 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 . The Gunners ' technical skills complemented with infantry field experience fundamentally posits them as advisers to the force commander s within the Fleet Marine Force ' s task forces ( i . e . Marine Expeditionary Force ( MEF ) and its subordinate units ) . Marine Gunners may be responsible for developing and monitoring weapons training protocols , tactical employment of weapons , preventive maintenance of the unit ' s infantry weapons , management of the units ammunition allocation — and the unit training plan , infantry training , and fire support planning . Additional assignments may be based on future needs of the Marine Corps ; such as new weapons systems acquisition , new weapons systems research and development . During combat operations , Marine Gunners assists their force commanders in battle tracking ; They are sent forward to oversee the battle , reporting directly to task force commanders in a " directed telescope " fashion . Billet Description and Core Competencies . The Marine Corps Infantry Training and Readiness Manual describes The Gunner as follows : The Gunner is a Chief Warrant Officer specifically trained in the employment and training of battalion organic weapons and assigned personnel . He is a special staff officer employed as the principal advisor to commander at all levels to assist in the development of training plans and employment of organic weapons . During combat , the Gunner may be tasked to inspect fire plans to ensure organic fires are integrated and mutually supporting at the battalion level , perform other supervisory tasks at critical events , and / or command task organized or provisional combat units . Gunners are advisors on the MOS training requirements and development of all MOS 0369 , 0313 , 0321 ( Infantry SNCOS ) . They have oversight of the unit ' s ammunition allocation and annual weapons re - qualification programs . They accommodate all weapons organic to the MAGTF in accordance the current version of MCO 3570 . 1 . Additional duties will include : new weapons systems acquisition , new weapons systems research and development , foreign weapons training , curriculum development for infantry MOSs and Marine Corps Marksmanship Programs , and Fire Support Planning . The Gunner ' s strength is his ability to vet , conduct and quantify combined - arms training . As infantry weapons officers advance in grade , billet assignments will include : Marine Gunner Plans , Policies & Operations Headquarters Marine Corps , Marine Gunner Infantry Training Battalion ( SOI East or West ) , Marine Gunner Advanced Infantry Training Company ( SOI East and West ) , Marine Gunner Marine Corps Ground Combat Operations Training Course , Tactical Training and Exercise Control Group ( TTECG ) MAGTF - TC , Marine Gunner Infantry Regiment ( Active and Reserve ) Marine Gunner Infantry Division ( Active & Reserve Component ) , Marine Gunner Infantry Officer Course , Marine Gunner The Basic School , and Marine Gunner Small Arms Weapons Instructor School . Additional assignments may be assigned based on future needs of the Marine Corps . History . Gunners were the first warrant officers in the Marine Corps when Henry Lewis Hulbert became the first Marine to pin on the Bursting Bombs on 24 March 1917 . Since that time the Gunner designation has undergone many changes including periods where no new Gunners were made from 1943 - 1956 , 1959 - 1964 , and 1974 - 1988 . These usually being the result of Gunners being promoted to Temporary Commissioned officer status or changes in the laws governing the rank structure of the military . Throughout this time few Marines have been able to rightly call themselves " Gunner " but though the list is short it is filled with legends of the Old Corps such as ; Henry Hulbert ; hero of Samoa , Belleau Wood , and Blanc Mont . A trophy bearing his name and image is presented to a Marine Gunner for Outstanding Leadership every year by the Commandant of the Marine Corps . Henry Pierson Crowe who talked General Julian C . Smith out of putting him in for a Medal of Honor after the Battle of Tarawa ( he received the Navy Cross instead ) . William Lee , the first Marine to receive three Navy Crosses but would spend World War II as a Japanese POW in China . Lee ' s father - in - law Calvin C . Lloyd for whom the rifle ranges in Quantico are named ; Though Lloyd retired a Major he always answered the telephone as " Gunner Lloyd " . There are other less well known , but important Gunners such as ; Ira Davidson , the " Daniel Boone of Iwo Jima " , who received a Navy Cross for taking out multiple Japanese pill boxes with uncanny accuracy while under withering fire . Gilbert Bolton who was himself decorated for valor with a Silver Star in Viet Nam for defending his platoon ' s position against a vastly larger NVA force by calling in six artillery missions on his own position and provided a link for the new breed of Gunners to the past .