Japanese anti-submarine shells for five-inch guns

Were Japanese anti-submarine shells for five-inch and lighter guns more effective than depth charges?

Probably not, though specialist shells gave smaller guns a plausible way to damage submarines and were credited with some successes.

Japanese specialist anti-submarine shells were credited with submarine sinkings, although those successes remain claims in this reply. They are judged probably less effective than depth charges. For five-inch and smaller weapons, special ammunition is considered necessary to have a useful effect underwater. Larger guns are judged less dependent on a specialist shell.