the MS 1908 if original is in 8x56 MS, the 1905 is in 9x56 MS but not in 9x57 Mauser

the 9x56 and the 9x57 are very similar and in many guns interchangeable because of excessive chamber dimensions. this cartridges have the shoulder more or less in the same position but there are little differences. if you use a 9x57 mauser die its possible your brass is not correct for your special chamber.
do I understand you right that brass resized with your die set by using 9,3x57 Norma fits into your gun but brass by using 8x57IS will not do it???
please take a look at the max. base diameter of your brass. Norma 9,3x57 will have a very small base diameter around 11,70mm when 8x57 IS brass will go up to 11,95mm and that may the reason you get only resized Norma brass into your chamber. I have the same problem with a M 88 in 9x57 and a Husqvarna M 46 in 9,3x57 where I have to turn 8x57 IS brass down to 11,70mm on the lathe to get it into the guns

9x56

9x57

9,3x57