 Sources disagree regarding these guns' performance, but naval historian Giorgio Giorgerini says that they fired armor-piercing (AP) projectiles at the rate of one round per minute and that they had a muzzle velocity of , which gave a maximum range of .The secondary armament on the two ships consisted of sixteen 45-caliber guns, also designed by Armstrong Whitworth, mounted in casemates on the sides of the hull underneath the main guns.Their positions tended to be wet in heavy seas, especially the rear guns.