I'll quip here right quick and be off:
I have taken a Renown class down at long range with my deck gun. No pics to prove it as I was actually pretty stunned that the other ships couldn't see me. Anyway, from a long distance of say 6.5km or more I've been able to engage and sink targets in clear weather without being spotted. So it's just a matter of plinking away at them until they finally burst into flames and sink, or the ammo magazine runs dry.
The thing about simulations is that they are... simulations. Imperfect representations of reality, really. So it might not be too unusual to disable the main turrets on a battleship and proceed to chew her to bits in this game, as long as our Uboat stays outside a certain range and manages to put enough projectiles directly on target. Either of those two criteria are easily met under the right circumstances (no air cover, no other patrols around, good marksmanship skillage).
