That B-25 of your grandfather is I think a model B-25H. They had the bombadier compartment blanked out and had 8-50 cals mounted in the nose. Plus 2-50 cals on pods on each side of the aircraft. These saw extensive service in the Pacific against Japaneese convoys. According to what I read, the forward fire power could nearly cut a Japaneese transport in half. Then after turning the vessel into swiss cheese.....you drop a few 500lb bombs to finish the job.....
