Wierd Story
 

I really wish that I had paused the game and taken pictures to show y'all.
I was en route to Honshu, and it was a big storm (thanks to Pacific Environment 4 and ROW), any way i'm going through some really super thick fog and then bam! about 15m off to my right a Fubuki Destroyer appears but doesn't shoot, so I think , oh s*** I have to dive. I go into a crash dive, and look at the navigation map and it shows that the ship was sunk by me. I still really wish i had some pictures, i'm sorry. :doh: :o :o :doh:

You playing stock with PE mod or something else?

The storm might have sunk the ship but your close proximity may have awarded a sinking to you.

Sometimes I can't seem to figure how the game awards sinking credits. I have sank ships with torpedoes and with the deck gun and received no credit for it. It is a rarity but does occur once in a great while.
I struck a ship the other day and she sank pretty much everything but the last 20% of the bow. I surfaced and used the deck gun to ventilate her and after about 50 shells she still had not gone down or registered as sunk.

I couldn't justify wasting more ammunition so I left.

Way I see it....