It was found that the primer composition of the M.90 was too corrosive, so the M.90/03 was introduced with a reduced mercury fulminate composition from 48.8% to 40% of the primer load. The copper (tombak) primer cup was also changed to brass with a black primer annulus. The paper patched lead bullets were loaded for match shooting with the military rounds having the CN cup with paper patch.
The B signifies that the case was supplied originally by the BERNDORFER METALLWARENFABRIK
Above three specimens are match loadings
The first specimen is probably a very early M.90/03 loading with the flat copper primer and black p/a, meaning that the primer composition might have been changed by this time, compared to the second specimen that has the brass primer
Training dummy with brass bullet and a spring loaded brass primer
Sporting/Match load
SFM Board dummy
SFM Sporting load