As other posters already mentioned above, you will run into feeding problems if you use shorter and/or pointed bullet cartridges in M03 Mannlicher – Schoenauers. Schoenauer's famous spool magazines, as used in the M 1900, 1903, 1905, 1908 and 1910 models, guide the cartridges around the spool at the cartridge's base and the round nose bullet tip. If you use cartridges with a shorter oal or a slim pointed tip the front end of the cartridge will drop away from the cartridge carrier and bind up in the magazine. As the cartridge retainer and feed ramp are also set up to feed the long, round nose bullet original loads, you will run into feeding problems if you try to use cartridges markedly under maximum over all length in a Mannlicher – Schoenauer magazine of the models listed above.
I rarely crimp any rifle cartridges at all, except heavy, 9.3x74R and up, double rifle loads. Even in my .416 Rigby and .458 Lott I never encountered bullet movement from recoil. Contrary to your belief crimping does nothing to "even out neck tension", more often it does just the opposite: Unless all cases are EXACTLY of the same length and chamfered exactly the same, you will end up with different crimps from case to case, setting up the quite uniform neck tension you get when using cases of the same lot, sized and expanded in the same dies to the same inside diameters.