When I go to crew management I can't drag any personell of any kind to the deck gun and choosing man the gun or selecting a target does nothing. Also it has a slot for an aft gun which I don't have in addition to my fwd deck gun and AA which does man just fine. I've done this at general quarters and not, during different watches ect. Using stock 1.4, uss drum. Yes I did make sure I was fully surfaced and had calm seas. It loads slow too.
You have run into the deck gun bug. when you started this campain, I'm guessing you had the deck gun mounted aft, and at some point, moved it forward. That it what likely caused you to loose the gunner slots. The only way to fix it is to reload a past save from before you moved the gun, and leave it aft, or you can start a new game and mount it up front from the getgo.
I have the same situation, they gave me a Gato class sub, and I moved it from aft to forward. I can't man it either, however, I prefer it that way as I don't miss as often a my crewman did when it was manned. He is all over the place when he shoots, I make sure we are pretty close, and I just fire away.
Thats good to know. I hope I'll get a new one the next time in, closing in on 100k assuming I survive the strait. Hoping the next one has duall AA as well.
For what it's worth, mount the 40mm's when they become available. They are very effective against merchants and escorts. I'm not sure about this, but I'm thinking the game just records shell hits to determine when a target sinks, and the 4 round clips let you put a lot of rounds on target in a really short amount of time.
I had one in a quick mission...pitty I didn't see those kate's dropping torpedo in time or I could have had some nice target practice. I was looking too high...the rest had bombs.