 The 305-millimeter guns were bored out to 320 millimeters (12.6 in) and their turrets were modified to use electric power.They had a fixed loading angle of +12 degrees, but there is uncertainty on their new maximum elevation, with some sources citing a maximum value of +27 degrees, while others claim one of +30 degrees.The 320-millimeter AP shells weighed and had a maximum range of with a muzzle velocity of .