戦艦アイオワ級の主砲命中率　(実弾射撃演習に基づく数字)

距離　30,000 yards (27,432 m)で命中率2.7パーセント　
http://www.navweaps.com/Weapons/WNUS_16-50_mk7.php

ただ実戦ではもっと低くなる可能性も有る

>　The data used to calculate these probabilities came from target practice shoots carried out by the battleships.
As such, I would suspect that under actual battle conditions that these values would be on the optimistic side.