I tend to use up my rear torps on the way to the patrol area, and then use my frontal ones to rip apart convoys.
Man, I love it when you hit a fuel carrying tanker.... the explosion... so satisfying. Unless its stormy weather and you had to get so close that the explosion causes a bad case of "death" to your sub.
Edit : Wait wut. My title thing and picture, I fear no man... but that... thing.... it scares me
