were tested (8 mm, 7.5 mm, 7 mm, 6.5 mm etc.), the optimal caliber was determined to be 6.5 mm (0.256 in). Following this decision, a joint Norwegian-Swedish commission was established in December 1893. This commission worked through a series of meetings to decide on the different measurements for the cartridge case. The Norwegians early presented a 6.5 mm rimless cartridge design, but the Swedes wanted a rimmed cartridge. As a compromise, the Norwegians produced an experimental semi-rimmed cartridge which was very similar to what would become the final version. The book Cartridge Cases refers to this cartridge as 6,5mm Norwegian Experimantal. This cartridge had a 6.7 mm bullet, a 55 mm long case, but differed from what became the final version by having a slightly less tapered shoulder, a slightly smaller diameter base (11.75 mm) as well as being semi-rimmed (12.6 mm). However, after a firearm demonstration by Mauser, the Swedes changed their mind and wanted a rimless design. After further discussions, a rimless cartridge case of 55 mm length was approved, and each possible measurement (diameter at base, diameter at neck, angle of case, angle of shoulder etc.) was decided upon. The corresponding dimensions of the cartridge chamber to be used in a future service rifle was also determined. At the time of its development the 6.5×55mm was a high-performance smokeless-powder cartridge. The design of the joint Norwegian-Swedish commission was subsequently adopted by the Norwegian and Swedish governments, and entered service in the Norwegian and Swedish militaries. The cartridge was also adopted by the Danish, Norwegian and Swedish civilian shooting associations DDS, DFS and FSR. In 1984, the C.I.P. independently standardized the cartridge as , and revised their standard in 2002 and 2007. In 1990, a specification was introduced along with the Scandinavian target rifle by the Scandinavian shooting associations DDS, DFS and FSR with the designation which tightened up the original tolerances (minimum and maximum dimensions) of the 1893 design standard, added a slightly longer chamber space for the neck for increased safety with untrimmed reloads, and increased the pressure rating. The SKAN chambering is approved for firing any 6.5×55mm cartridges satisfying the aforementioned C.I.P. and SAAMI standards. In 1993, the SAAMI also independently standardized the cartridge as 6.5×55mm Swedish, with the official SAAMI abbreviation being 6.5×55. The closest European and American ballistic twins of the 6.5×55mm are probably the German 6.5×57mm Mauser and the American .260