 The main armament of the Active class consisted of ten breech @-@ loading ( BL ) 4 @-@ inch ( 102 mm ) Mk VII guns . The forward pair of guns were mounted side by side on a platform on the forecastle , six were amidships , three on each broadside , and the two remaining guns were on the centreline of the quarterdeck , one ahead of the other . The guns fired their 31 @-@ pound ( 14 kg ) shells to a range of about 11 @,@ 400 yards ( 10 @,@ 400 m ) . Her secondary armament was four quick @-@ firing ( QF ) three @-@ pounder ( 1 @.@ 9 in ( 47 mm ) ) Vickers Mk I guns and two submerged 18 @-@ inch ( 450 mm ) torpedo tubes . 
