 These ships would have rivaled the Imperial Japanese Yamato class and America 's planned Montana class in size if any had been completed , although with significantly weaker firepower : nine 406 @-@ millimeter ( 16 @.@ 0 in ) guns compared to the nine 460 @-@ millimeter ( 18 @.@ 1 in ) guns of the Japanese ships and a dozen 16 @-@ inch ( 406 @.@ 4 mm ) on the Montanas . However , they would have been superior to their German rivals , the Bismarck class , at least on paper . The failure of the Soviet armor plate industry to build cemented armor plates thicker than 230 millimeters ( 9 @.@ 1 in ) would have negated any advantages from the Sovetsky Soyuz class 's thicker armor in combat . 
 These ships would <a href='been_done' title='1'><mark>have</mark></a> rivaled the Imperial Japanese Yamato class and America <a href='null_genetive' title='2'><mark>'s</mark></a>planned Montana class in size if any <a href='been_done' title='3'><mark>had</mark></a> been completed , although with significantly weaker firepower : nine 406 @-@ millimeter ( 16 @.@ 0 in ) guns compared to the nine 460 @-@ millimeter ( 18 @.@ 1 in ) guns of the Japanese ships and a dozen 16 @-@ inch ( 406 @.@ 4 mm ) on the Montanas . However , they would have been superior to their German rivals , the Bismarck class , at least on paper . The failure of the Soviet armor plate industry to build cemented armor plates thicker than 230 millimeters ( 9 @.@ 1 in ) would <a href='been_done' title='4'><mark>have</mark></a> negated any advantages from the Sovetsky Soyuz class <a href='null_genetive' title='5'><mark>'s</mark></a>thicker armor in combat . 
These ships would done rivaled the Imperial Japanese Yamato class and America  planned Montana class in size if any done been completed , although with significantly weaker firepower : nine 406 @-@ millimeter ( 16 @.@ 0 in ) guns compared to the nine 460 @-@ millimeter ( 18 @.@ 1 in ) guns of the Japanese ships and a dozen 16 @-@ inch ( 406 @.@ 4 mm ) on the Montanas . However , they would have been superior to their German rivals , da Bismarck class , at least on paper . Tdafailure of the Soviet armor plate industry to build cemented armor plates thicker than 230 millimeters ( 9 @.@ 1 in ) would done negated any advantages from the Sovetsky Soyuz class  thicker armor in combat .