gunsaholic,
After the war, the Germans were required to turn in their guns to the allies, under penalty of death if caught with a gun( at least so threatened). The turned in guns were generally destroyed by various methods, and many were brought home by returning GIs as war trophies. This is how most of the prewar drillings we collect were saved from destruction. Naturally, this was resisted in many cases. The scope and or forearms were removed from many of the guns before turning them in, as resistance to the order, and to save the valuable scope, as well as making them un-appealing to GIs. We know now that a great many were hidden, rather than turn them in. Some of the hidden ones were buried in the ground, well protected, and some not well protected. There is a good chance this drilling was one of those buried, without adequate protection. I have and use one that was also buried. The barrels of mine were in bad shape, but unlike the one here, had a DURAL ( aluminum alloy) receiver which did not rust and protected the internal parts. After rebarreling, restocking, and mounting a new scope, mine is serving me as well as it did it's previous owner. A very good late hunting friend of mine buried 5 of his guns under his house in Erlangen. While he was working over a hundred miles away, someone told the authorities that he had not turned in his guns. They searched his house, which upset his wife so much she made him dig them up an throw them into the Main River, when he did come home. There is little doubt your drilling has a story, too bad it can't talk.
Mike