After reading your rendition of the testing of the forward gun mount, I recall the said incident from a different perspective. As a member of the misfire party stationed on the other side of the "door" during gun shoots, the event has a slightly different feeling.
Imagine yourself sitting on the main deck, garbed in the appropriate fire-fighting outfit, holding a fire hose awaiting for the moment of misfire when your sole purpose is to place the end of the hose into the mussel of the five inch gun. Sitting there waiting for that moment to occur tends to allow for allot of contemplation time. Mostly we were half asleep. The gun had been firing rounds most of the day and we were lulled into a false sense of security.
The door in question, as I remember had two dogs and a door knob. The dogs had worked loose during the previous shots, but no-one had noticed. As the testing progressed, the mount was testing a five round salvo aimed just below the safety interlocks. The first round vibrated the structure, just like normal, and the door opened. The next four rounds went into the now opened door and tried to rip it off the super-structure, causing the super-structure to become mangled and causing the misfire team to have to report below decks to change pants. Thank God that the rounds where only cork rounds. I also remember that we pulled in following this incident stern toward the pier so that the shipyard could fix the super-structure, and not advertise that we shot ourselves. I also remember that following our arrival, someone painted a door on the forward gun mount, which did not sit too well with Capt. Davis.
CWO3 Mike Ihrig