https://www.armagcorp.com/products/weapons-storage/arms-weapons-storage/ I'm guessing that the Armag was solely used by the USAF facility security unit. IIRC Incerik is actually a Turkish AF base with base security by the Turks. Without a robust USAF security capability on base, I can't imagine we would have much if any presence there any longer.
You are correct - an Armag vault is for small arms. Two years ago my company had a contract to completely remodel an existing building on a U.S. base that contained among other things a small arms armory. Part of our contract was to prep an area for the installation of the same size Armag vault and to assist in its installation for their use while we were remodeling the rest of the bldg.
I have a friend who is a pilot and served at Incirlik. It was not a good duty station. Nobody liked being there.
Nice website, I could use one of these.