I am presently working on loads for a Spanish arsenal built 1880's rolling block rifle.  Spain paid Remington for the rights to build these rifles at their Oviedo arsenal, but also copied some features from the Danish rolling blocks (that were also licensed from Remington).  These military rifles show high quality of materials and workmanship, unlike the later stuff made outside of the Spanish arsenals for various civilian markets.  Spain started out in the early 1870's with what we today call the .43 Spanish black powder cartridge, but by the mid-1880's changed over to a locally developed modified cartridge called the .43 Spanish Reformado (reformado means "reformed" or modified).  Virtually all Spanish military rolling blocks were converted to this cartridge in the late 1880's, but I have found no reference or examples of the western hemisphere .43 Spanish rolling blocks being converted-most of Spains former new-world holdings were independent by this time.  However, it is suspected that Spanish rolling blocks so chambered would have been shipped to Cuba and other remaining Spanish colonies in the next decade (1890's) as Spain rearmed main-line troops at home with 7mm Mauser (7x57mm) bolt action repeaters.

 

The original .43 Spanish case has a slight bottle neck, while the modified Reformado design has a straight tapered profile much like a .45/70 case.  There are .43 Spanish cases and reloading dies currently available, but I have found no sources for .43 Reformado supplies.  The barrel / chamber cast I made measures .451 in the bore just ahead of the chamber, so I'm planning to start with a mold for the .45 Colt pistol cartridge.  My thinking for cases at the moment is to start by turning the belt off magnum cases (I have a bunch of 7mm Rem Mag cases) and then press on a collar cut from brass tubing that will be a press fit against the remaining case rim. A proper larger diameter rim will then be turned from this press fitted collar.  A bunch of screwing around, but the resulting cases should be a perfect fit and wonderfully strong by black powder standards.

 

More to follow on this project when I get more time to work on it, and take some pictures!