The class was designed to carry twelve 14-inch guns in three quadruple turrets and this configuration had a heavier broadside than the nine 15-inch guns. It proved impossible to include this amount of firepower and the desired level of protection on a 35,000 ton displacement and the weight of the superimposed quadruple turret made the stability of the vessel questionable. The second forward turret was changed to a smaller two-gun turret in exchange for better armour protection, reducing the broadside weight to below that of the nine gun arrangement. The 14-inch Armour Piercing (AP) shell also carried a very large bursting charge of . The armour-piercing capability of the gun and its ammunition is exhibited by the conning tower on the wreck of the German battleship "Bismarck", provided with 14-inch thick armour, which is said to resemble a "Swiss cheese". The last naval treaty had an escalator clause that permitted a change to 16-inch guns if another signatory did not conform to it by 1 January 1937. Although they could have invoked this clause, the effect would have been to delay construction and it was considered prudent to build with 14-inch rather than find themselves without the new battleships. The U.S. opted to absorb a delay and built its ships with larger guns. When comparing the British 14-inch gun to the heavier guns mounted on contemporary foreign battleships, the thicker armour of the British battleships tended to result in an equalisation of the relative penetrating power of respective shells.