Since the previous owner was into stashing firearms.
Was he an old guy who mighta had memory problems ???
Or dead and you bought the property from people who inherited it???


Either way....
You might wanna spend some time metal detecting that place.
Conspicuous or innocuous landmarks
Lone trees.
Rises on ground.
Areas around buildings.


To delibrately hide guns like that and you discover em.
Probably other stuff around the place to be found no one had any idea of when you bought the place.