GG:

I don't own a M/S but have always read that ALL magazines {spools} are precisely made to fit one specific cartridge and to guide it into the chamber, with each and every cartridge possessing a specific magazine. Supposedly this is much more of an issue with the M/S than it is, say, with a Mauser. Can't remember the cite offhand, maybe deHaas? Thus, changing caliber/cartridge is said to be very difficult with the M/S action for that reason, with very slight differences in spool dimensions impacting feeding reliability significantly.

Guy's is that true? Or for example, could a .30-06 M/S be rebarreled to 9.3x62 or some similar swap?