Aktungbby,
Thank you for looking into that for me! Very cool info... makes me want to have a cold beer on the cigarette deck to "splice the main brace!"
The "gun ammo storage", or main magazine is in the crew quarters/gally I believe... so this does go into the pressure hull from the cigarette deck. I am amazed at the engineering and technology used during this time period! These subs were really advanced for their time. I was just reading about the "Blast-phones" used to identify the direction of exploding depth charges.
Thanks again for the research on this!