5.5 X 50 BELTED AUSTRIAN XPL

Research notes

This is one of a small number of cartridges developed from a March 1891 patent by the Austrian firm of Georg Roth whereby a belt is added to the extractor groove in order to facilitate headspace in the new chambers. This was a radical design for its era as this was the period of transition from black powder to smokeless and rimmed cartridges in single shot rifles converted from rimfire to rimless bolt action rifles by the likes of Mauser. The belted case design allowed for greater chamber pressures translating to better ballistic performance as well as various caliber reduction experiments and the design of steel cases. Very little, if any, information is available in terms of military test data as these experiments were largely driven by research and development by the private sector (G. Roth) in terms of innovation free from bureaucratic red tape, a concept that will probably never change.