I prefer this machine, just because I love the m1 garand. Always been my favourite semi-auto to use in wwII games.
The vault armory should be easy to find, just go downstairs and follow the corridors. Now getting into the vaults a different story. Nice little puzzle.
the vaults aren't that large. the confusion is the levels in each section show up on the game map as one level.
the room that perhaps is causing the most problem is the one with the safe. it has two entrances/exists. some of the rooms do look alike when going around in circles.