Adapted from A.L.Raven's design drawing. The Montana was designed to have 4x 3-gun 16"/50cal Mk7 (same guns used on Iowas) and 10x dual 5"/54cal as secondary batteries. Five ships were planned, but none were laid down as Iowa-class battleships and Essex class carriers were given priority.
http://en.wikipedia.org/wiki/Montana-class_battleship