Is the bolt face only there to centre the cartridge during feeding, or is it also supporting the rim of the cartridge so that it doesn't deform? I suspect it would be a bad idea to use the same bolt face for 9mm Parabellum and 10mm Auto, but I want to be sure.
And I've found this: https://www.thetruthaboutguns.com/2015/06/jeremy-s/40-in-a-10mm-glock/ Maybe it really is a problem solver if you want a multi-caliber firearm.