No circle 20 but instead a 20/70 stamp. A stamp of "A/DAHA" on the lug. Nitro stamp but no 1 in a circle. All the crowns you mentioned are present. SPEZIAL-GEWEHRLAUFSTAHL on barrel. An enclosed U symbol with a hammer through an oval?

I live close to the border of Kentucky, in a area called Floyds Knobs, IN for the last 11 years. Prior to that I lived in Hondo and Midland, TX.