Board Thread:Off Topic/@comment-25730832-20160122165904/@comment-68.191.49.101-20160126204957

We don't know if a ship needs to be swimming with the fishes or have been turned into kitchen utensils to come back as a shipgirl, or even if they are actual reincarnations at all. The "setting" of the game is not entirely fleshed out, and for all we know, it never will be, the devs being satified with keeping the ambiguity intact and the mystery unanswered.

Also, the guns can only be found on the Iowa class battleships, and while not to say it's impossible they will appear on another ship, but when the name, Iowa class, is written in the description, I figure that is all the evidence we need.