In 1893, Mexico adopted both a revolver and a revolver carbine produced by Henri Pieper of Belgium. According to some sources, these were chambered for two different for proprietary cartridges of 8 × 41R mm (some sources say 8 × 37R mm, but this seems incorrect) and 8 × 50R mm (or 7.9 × 50R mm), respectively.
Most other sources (e.g. James Hughes’ Mexican Military Arms: The Cartridge Period, 1866-1967, 1968) indicate that both weapons were chambered for the same “8mm Pieper” cartridge.
Can anyone confirm either way? Does an 8 × 50R mm Pieper exist, or is this mislabelled? Which weapon(s) was it used with, if it is indeed real?