The answer to your original question is yes, you can turn the rims of a .30BR to work in a PPC boltface. One of the cheap mini lathes will do it, or you can do it slowly, carefully without a lathe.
There is another possibility -- probably, BAT can open up the boltface you already have, and provide two extractors, one for the PPC one for the BR, and you can use both cases, unmodified. Two of my 2-lug BATs (for PPC) have .308 -- or as us oldtimer's liket ot say, .30/06 -- boltfaces. This would be far less expensive than a second bolt.
BTW, a couple of people have used a PPC with an 8-twist barrel & 100 grain bullets. Check the 1.000 yard archives, or ask Cheechako or Roger Haney. You can use cheaper bullets & cheaper powder with such a PPC, leaving the only "expensive" component the cases. And if you are not pushing the cases real hard, they will last a long, long time. I beleive Roger Haney was getting a bit over 2,900 with a 105 grain bullet in the PPC, using 748 and 4895 -- but check.