This was proofed at the Eckernforde (Kiel) proof house after 1952. The Eckernforde mark from '52 to '68 was an oak leaf after '68 it is a sytlized oak leafdifferent from the Kiel mark on this drilling. I believe there is a '66 date on the rifle barrel. The circular mark just in front of the "30-06 Spring" on the bottom of the rifle barrel, I can not make out. Are there any triangular marks with letters or a number within the triangle? The letter marks on each barrel are likely the initials of the barrel maker or inspector. Gauge and chamber length are self explanatory. This was made for export. Show us some pics of the rest of the drilling. Looks like a nice piece!!