My buddy just picked up a 9.3x57 Oberndorf with matching serial numbers that puts it manufactured in 1924-1925. But the proof marks include the crown over N and there is an extra set of proofs on the left with the top proof I can’t make out. I understand the crown over N proof didn’t start until the late 1930s.
So how does the 1925-25 date of manufacture work with the crown over N and what is with the extra set of proof marks?