Joel, forgive me if I appear overcautious, even a bit picky, but I would be grateful if you would acknowledge the following disclaimer before firing that rifle with live ammunition:
The advice given with regard to the refurbishment of the ArgentineRolling Block chambered in caliber .43 Spanish and the method of making ammunition for the same does not imply any responsibility for the safety of the aforementioned rifle and ammunition. Every shooter and reloader is himself or herself responsible for the safety of the guns that they use and the ammunition that they employ. In case of doubt, the only proper course is to consult a professional gunsmith.
Patrick