I'm back.... Sorry about the wait. To answer a few questions...
It is mid-1940 with a stock Type VII. And I am welll aware of the coming dangers! All I can say is hit it while you can get it!
I usually save at the point when I contact a convoy; not in the midst of it and not when submerged. Not very sporting.
Anyway. I got a belly shot on the Nelson just below the aft turret and it went down like a rock by the stern... 10 minutes or so. I also salvo a large cargo and hit it. BTW, what is with the retarded Destroyers anyway? It's clear weather and once I hit the Nelson, it darts to the rear of the convoy and starts a search... 2Km away!!!
So in all, over a 2 day running battle, I use all Torps and all Gun ammo and all I get only 96,400 tons.
Dammit! I missed the 100 K club. Oh well. I'll just get it next mission. Happy hunting, Y'all.