I have received an inquiry about what appears to me from the description must be a 13 x 64B cartridge. I know nothing about these. The headstamp is “awt 43” which I found is from Silva Matallwarenfabrik, Werk Magdeburg, and the Projectile and primer are coded “nhr” which seems to be Rheinmetall. Reported are the remains of a black neck seal and a black primer seal with no other painted markings. the steel bullet is pointed and does not have any separate nose cap, nor does the Diameter of the bullet reduce about 1/3 of the way down from the tip like those shown in drawings in the Dutch book on case types.
I know this isn’t the best description, but it is all I have. Can someone identify the loading of this round?