Hmmmmm . . . .
These cases that bulged were shot out of a 44 mag Taurus raging bull. I'm not sure the formulas that were in these particular cases. I never go over the max recommend by the charts, however I've been getting close to the max. I check the powder measure with a scale after every ten loads.
I suppose it's possible that a couple 44 somehow slipped in with my 45C but I can't imagine how it happened. I can think of only one trip to the range this last year that I even had the 44 and the 45 along on the same trip.
Anyway, if the case is not split, no head separation etc. then the bulge alone is not a reason to discard the brass?
Live well, be safe