Designed for the Mogami class cruisers to serve as a dual-purpose main battery, these guns also served on the Yamato and Musashi as a secondary battery, on the Oyodo light cruiser as the primary battery, and would have also served on the Tone class but the design was un-gunned like the Mogami's were. In the case of the Yamato's and the Oyodo, these ships were the only ones to go to war with these guns.

Around 80 of these guns were manufactured at Kure Arsenal. While they were intended for dual-purpose use, their slow rate of fire and poor elevation, couple with a slow training speed, made them lackluster in anti-aircraft use.

These barrels must be trimmed at the first barrel sleeve, not flush with the barrel assembly.