 The ships also carried twelve 8 @.@ 8 cm ( 3 @.@ 45 in ) SK L / 30 quick @-@ firing guns , also mounted in casemates and pivot mounts . These guns were supplied with between 170 and 250 shells per gun . These guns fired 13 @.@ 8 kg ( 30 @.@ 4 lb ) at a muzzle velocity of 590 mps ( 1 @,@ 936 fps ) . Their rate of fire was approximately 15 shells per minute ; the guns could engage targets out to 10 @,@ 500 m ( 11 @,@ 480 yd ) . The gun mounts were manually operated . The ships ' gun armament was rounded out by twelve machine cannons . 
