▁The ▁gun ▁was ▁first ▁used ▁in ▁the ▁later ▁stages ▁of ▁the ▁Vietnam ▁War ▁and ▁is ▁still ▁used ▁in ▁the ▁AC - 1 3 0 U ▁gun ship . ▁The ▁latest ▁AC - 1 3 0 J ▁Ghost r ider ▁gun ship ▁was ▁not ▁originally ▁planned ▁to ▁include ▁the ▁ 1 0 5   mm , ▁but ▁designed ▁with ▁enough ▁spare ▁power ▁and ▁room ▁to ▁mount ▁it ▁at ▁some ▁later ▁point . ▁ ▁The ▁Air ▁Force ▁decided ▁to ▁include ▁it ▁in ▁January ▁ 2 0 1 5 , ▁starting ▁installation ▁on ▁the ▁third ▁aircraft , ▁then ▁having ▁the ▁first ▁two ▁be ▁retro f itted ▁when ▁guns ▁become ▁available ; ▁M 1 0 2 s ▁will ▁be ▁pulled ▁off ▁ret iring ▁AC - 1 3 0 Us ▁and ▁put ▁into ▁the ▁AC - 1 3 0 Js . ▁ ▁The ▁M 1 0 2 ▁is ▁used ▁in ▁extremely ▁limited ▁roles ▁by ▁the ▁United ▁States ▁Marine ▁Corps , ▁primarily ▁for ▁firing ▁sal utes . ▁ ▁The ▁Malays ian ▁Army ▁used ▁the ▁M 1 0 2 ▁during ▁Malays ia ' s ▁second ▁commun ist ▁ins ur gency ▁( 1 9 6 8 – 1 9 8 8 ) ▁to ▁bomb ard ▁ins urg ent ▁positions ▁on ▁the ▁Malays ia - Th ailand ▁border . ▁The ▁guns ▁were ▁transport ed ▁by ▁hel ic opter ▁to ▁remote ▁firing ▁positions . ▁All ▁Malays ian ▁M 1 0 2 s ▁have ▁now ▁been ▁de comm ission ed ▁and ▁are ▁only ▁used ▁for ▁firing ▁sal ute . ▁ ▁Character istics ▁▁▁ ▁C