 The Ruggiero di Laurias were armed with a main battery of four 17 in ( 432 mm ) 27 @-@ caliber rifled <unk> guns , mounted in two pairs en echelon in a central barbette . These guns were the A 1882 model , and they fired a 2 @,@ 000 @-@ pound ( 910 kg ) shell at a muzzle velocity of around 1 @,@ 837 feet per second ( 560 m / s ) . Their rate of fire was very slow , taking eight minutes to reload after each shot . They carried a secondary battery of two 6 in ( 152 mm ) 32 @-@ caliber guns , one at the bow and the other at the stern , and four 4 @.@ 7 in ( 119 mm ) 32 @-@ caliber guns . The 6 in gun fired a variety of shells , including 102 lb ( 46 kg ) armor @-@ piercing shells , while the 4 @.@ 7 in guns fired 36 lb ( 16 kg ) shells . From 1900 , the ships had their secondary battery significantly expanded with two 75 mm ( 3 @.@ 0 in ) guns , ten 57 mm ( 2 @.@ 2 in ) 40 @-@ caliber guns , twelve 37 mm ( 1 @.@ 5 in ) guns , five 37 mm revolver cannon , and two machine guns . As was customary for capital ships of the period , they carried five 14 in ( 356 mm ) torpedo tubes submerged in the hull . The torpedoes carried a 125 kg ( 276 lb ) warhead and had a range of 600 m ( 2 @,@ 000 ft ) . 
