Thanks for the reply sniper, it makes sense. I think I have a general understanding now of all the elements of manual targeting (well as good as I can as I SUCK at math and am generally useless

)
As for the tonnage, I guess my "gripe" is that I sink too much on a single patrol. Now sinking is fun and the aim of the game but always at the back of my mind knowing that I am sinking more in a single patrol than the top aces did over the entire war bothers me.
Guess I should look at some mods but guess the following things could help solve the situation
- Lower Tonnage Rating for ships (which I think happened after the war anyways, think a lot of skippers got their tonnage reduced by half post war)
- Reduce the amount of the high tonnage targets running around ungarded (i.e I met FOUR ungarded passenger liners, 2 modern, 1 large and one HUGE EU liner. Thats 2 x 9k tons, 1 x 7k tons and 1 x 19k tons)
- Reduce power of deck gun
I am sure there are mods that address this so will have a look...and then probably curl up and cry when I finish a only a single fishing boat sunk