If the sights & scope remained nice & tight & you were not using any lubes or oils for swabbing, then I suspect you were a victim of an overheated barrel. CVAs and Tradition rifles use softer steel. Shot changes are common when heated/overworked--typical ofmy three Traditions firearms.

Another suspect could be your powder interaction. Hard to pinpoint anything on my end since you never mentioned what powder you shoot, how much you used & what Powerbelt you used (Lead-copper). If you were using magnum powder loads, you may have lead, copper or plastic residue in your bore. If that's the case, get a good solvent that removes it & ALWAYS use a bore brush for swabbing& cleaning inlines.... not a jag.