 The main armament of the Nagato @-@ class ships consisted of eight 45 @-@ caliber 41 @-@ centimeter guns , mounted in two pairs of twin @-@ gun , superfiring turrets fore and aft . Numbered one through four from front to rear , the hydraulically powered turrets gave the guns an elevation range of − 2 to + 35 degrees . The rate of fire for the guns was around two rounds per minute . Their turrets were replaced in the mid @-@ 1930s using the turrets stored from the unfinished Tosa @-@ class battleships . While in storage they were modified to increase their range of elevation to − 3 to + 43 degrees , which increased the gun 's maximum range from 30 @,@ 200 to 37 @,@ 900 meters ( 33 @,@ 000 to 41 @,@ 400 yd ) . 
