I once owned that gun or one like it. I picked it up because I thought it would be a great platform for a custom upgrade project. I didn’t realize what the short strap on the stock was about until I pulled the stock off. Once I realized what was going on I had to leave it alone.
The next time I saw my old friend and longtime German gun collector Ross Munson. I said I think I have something you never seen before! He had not seen it before but he went home with it!
Regrettably Ross is no longer with us. But he was from MN so there’s a good chance it’s the same gun.