Unmarked/unstamped 7,65x54mm Mauser

I have a clip of unmarked/unstamped 7,65x54mm Belgium-Argentine Mauser.
No marks on the cases nor on the clip.
Are those cartridges from a special order or they forgot to stamp the cases?
I have them for many years and never find info about them.32191327_1802119889831452_2175478193295720448_n


Cupro nickel or cupro nickel clad steel jackets? Jack

Cupro nickel clad steel jackets, they are magetic.

Martin: Thanks for your response. I suppose I was hoping you would say “cupro nickel,” which would narrow the number of possibilities a good bit. Nothing very useful occurs to me apart from the thought these might have been produced for the Chaco War between Bolivia and Paraguay in the early 1930s. Good luck! Jack

Thank you very much Jack.
Any idea about origin?
It should be from European origin as Fabricaciones Militares (argentine ammo making industries) start on 1941, long after Chaco War was over.
Thank you very much.