Using the 1-2-3 system? if so it really is just a case if lining up the dots.... (from your boat to their sailing trajectory.) what i have noticed, is that putting your fish in the water strait on lets say the 3 and 3 dots (or any of the numbers) will score either "just" a bow hit or if you were a little hasty and shot infront of the dot a just miss of the bow.....
hope this helps, it's hard for long range shots but im able to pull the off now with approximate calculation in my mind as long as the ships don't deviate from coarse, actually gives a bit of tension....
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