I once saw an M70 that at first glance appeared to be marked .30 Gov't '03. Upon closer inspection, apparently the stamping tool was not completely in contact with the barrel when struck and the last digit was incomplete in such a way that it could be mistaken as a "3" by someone with a vivid imagination. Another possibility is that the barrel was refinished and enough metal removed around the cartridge designation so as to distort it to make it look like something it isn't.
I would have to see a quality photo of the subject rifle to actually believe it is marked 03. Not calling anyone a liar, just mistaken, though I could also be mistaken. It happened once.
