▁eight ▁r ounds ▁per ▁gun , ▁per ▁minute . ▁There ▁were ▁three ▁mount ings ▁the ▁two - gun ▁M k ▁XX I , ▁the ▁three - gun ▁M k ▁XX II ▁and ▁the ▁three - gun ▁M k ▁XX III . ▁ ▁Depending ▁on ▁the ▁mount ▁elev ation ▁limits ▁differ ed . ▁ ▁The ▁M k ▁XX I ▁tur ret ▁elev ation ▁limits ▁were ▁+ 6 0 ▁degrees ▁to ▁− 5 ▁degrees , ▁and ▁the ▁M k ▁XX II ▁tur ret ▁elev ation ▁limits ▁were ▁+ 4 5 ▁degrees ▁to ▁− 5 ▁degrees . ▁ ▁Lo ading ▁could ▁be ▁accomplished ▁at ▁any ▁angle ▁up ▁to ▁+ 1 2 . 5 ▁degrees , ▁although ▁the ▁preferred ▁loading ▁angle ▁was ▁between ▁+ 7 ▁and ▁+ 5 ▁degrees ▁for ▁all ▁three ▁mount s . ▁ ▁The ▁M k ▁XX I ▁and ▁XX II ▁mount s ▁used ▁a ▁" short ▁tr unk " ▁am mun ition ▁ho ist ▁while ▁the ▁M k ▁XX III ▁used ▁a ▁" long ▁tr unk " ▁am mun ition ▁ho ist ▁system , ▁which ▁reduced ▁the ▁crew ▁requirements ▁and ▁increased ▁the ▁speed ▁of ▁the ▁am mun ition ▁ho ists . ▁A ▁R N ▁g unn ery ▁officer ▁on ▁HMS ▁B erm uda ▁gave ▁details ▁of ▁the ▁loading ▁cycle ▁which ▁could ▁be ▁att ained ▁in ▁the ▁M k ▁XX III ▁tur ret ▁with ▁a ▁well ▁trained ▁crew : ▁"... a ▁loading ▁cycle ▁of ▁four ▁and ▁a ▁half ▁to ▁ 5 ▁seconds ▁was ▁att ained ▁at ▁low ▁elev ation , ▁another ▁two ▁to ▁three