You are right about the Circle Z being on these rifles. HOWEVER, this rifle has no German proofs. It does have a Circle Z stamping. Perhaps a 1945 rifle might not have proofs, but I doubt the Germans would have let it out the door that way in 1944. Perhaps a 1944 set-aside receiver? Perhaps a factory second receiver? I am guessing that all good quality 1944 production went off to war ASAP. Just not sure about this one. Interesting rifle for sure.