good buy, best allround cartridge ever!

I have a problem with the fact it was made as a 9,3x64 in 1951. before WW 2 the 9,3x64 was a proprietary cartridge only made by Wilhelm Brennecke Leipzig. we can assume that no ammo was made after 1941/42 and it was allways rare. in 1951 nobody could anticipate it was ever made again. I have no data but it cant be before 1955/56 that DWM start's the production.

so the action was made by FN in 1951 but I believe the whole rifle was build together some year's later.