Some of the massive turning lathes used for 16" gun barrel work were saved and relocated to the (long gone now) Naval Ordnance Laboratory in White Oak MD. Buddy of mine got a job there right out of HS in 1976 and was trained to operate those. I got a chance to see them up close during an open house at the lab.
All those wonderful machines are scrapped now...as are all the spare 16" gun barrels we had in inventory.