of . Armament Dreadnoughts main armament consisted of ten 45-calibre BL 12-inch Mark X guns in five twin Mark BVIII gun turrets. The forward turret ('A') and two aft turrets ('X' and 'Y') were located along the centreline of the ship. Two wing turrets ('P' and 'Q') were located port and starboard of the forward superstructure respectively. Dreadnought could deliver a broadside of eight guns between 60° before the beam and 50° abaft the beam. Beyond these limits she could fire six guns aft, and four forward. On bearings 1° ahead or astern she could fire six guns, although she would have inflicted blast damage on the superstructure. The guns could be depressed to −3° and elevated to +13.5°. They fired projectiles at a muzzle velocity of , giving a maximum range of with armour-piercing (AP) 2 crh shells. Using the more aerodynamic, but slightly heavier, 4 crh AP shells extended the range to . The rate of fire of these guns was about two rounds per minute. The ships carried 80 rounds per gun. The secondary armament initially consisted of twenty-seven 50-calibre, quick-firing (QF) 12-pounder 18 cwt Mark I guns. The guns had an elevation range between −10° and +20°. They fired projectiles at a muzzle velocity of . The guns had a rate of fire of 20 rounds per minute. The ship carried three hundred rounds for each gun. The original plan was to dismount the eight guns on the forecastle and quarterdeck and stow them on chocks on the deck during daylight to prevent them from being damaged by muzzle blast from the main guns. Gun trials in December 1906 proved that this was more difficult than expected and the two port guns from the forecastle and the outer starboard gun from the quarterdeck were transferred to turret roofs, giving each turret two guns. The remaining forecastle guns and the outer port gun from the quarterdeck were removed by the end of 1907, which reduced the total to twenty-four guns. During her April–May 1915 refit, the two guns from the roof of 'A' turret were reinstalled in the original positions on the starboard side of the quarterdeck. A year later, the two guns at the rear of the superstructure were removed, reducing the ship to twenty-two guns. Two of the quarterdeck guns were given high-angle mounts for anti-aircraft duties and the two guns abreast the conning tower