Say if you are in a cruiser shooting 6 inch rounds at a destroyer, Ap rounds will often go right through and out the outher side.
there are more than 1 type of Ap as there are many kinds of explosive shells as well. My father was RN (Gunnery Branch)
as were 3 generations on his side of the family. So you could say it is kind of a "family tradition" to serve.
The main round used by RN during WW II was actually a "dual purpose" shell that was basically a HE round with a "hardend" cap.
A number of diffrent fuse settings were available and shells were usually "set" at the gun just prior to loading.
I suppose it is my fault for Generically reffering to them simply as "HE". I do this as i find most people are generally bored and not
very intrested with actual fact historical or outherwise.