Prolonged use of shorter case will create some kind of residue build up. If not removed prior to shooting 454 round, you might be able to slip loaded round in the chamber, but after bullets starts to move, case crimp will try to open but deposit is there… Without going in too many details, already very high 454 pressure will go much higher, and even incredibly strong FA revolver could blow up. With a number of powders available today, you can load 454 from mild to wild, just do not use any of the fillers in reloading, see
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