My dad flew on B-25's with the 75MM, and they were used for anti-shipping. He said that it felt like the bomber stopped flying for a second. They were pretty hard on the airframe too.
Originally Posted by Castle50
Their night fighters (PV-1's) were equipped with .50's, and against the typical Japanese aircraft, they were deadly.
He was not as impressed with the single .30 in the belly of the TBM. He went for a couple of "rides" (he was bored and a Marine = extra missions) and said it was not very effective against the Zeros who came up to spoil the the fun.
He attacked everything in life with a mix of extraordinary genius and naive incompetence, and it was often difficult to tell which was which.