I am currently on the a second part of my current patrol and making my way to East China Sea. I encountered 2 Japanese destroyers, so I decide to raise their stress level a bit. I target the trailing ship from 7000+ yards and send 3 fish his direction. I think I read somewhere on these forums that their hulls do not go very deep in the water, so I set all 3 fish to shallow. The first fist hit and sank its target. A few seconds later the 2nd hit the already sinking ship. The 3rd torpedo missed (with was pretty obvious). I immediately set my sights on the remaining destroyer and it did not seem to phase him that his buddy sank. He just kept making a tight counter clockwise circle at a constant 15 knots.
How would I target him and get a good firing solution? Prior to me targeting the 2nd destroyer, I saved the game and sent 2 fish his direction but of course they both missed. I am currently sitting at periscope depth about 4500 yards from him with my stern facing him. Do I surface and send some deck guns shells his way or would I just sit there patiently and wait for him to break his circular pattern?