I'm not sure I'd change a thing from what I have. A couple of Borden Rimrocks in the Borden/Adamowitz(sp) style stocks(still my favorite), a very good old Jewell trigger and a GREAT barrel. Call me happy with that. As for cartridge, I believe a 30BR and 30 Major are a coin toss and there are other obscure wildcats that are probably just as suitable.. Of course, 13.5lbs 30 cal for IBS/NBRSA. Oh, almost forgot the scope. Hard to beat a NF 15-55 but there are certainly other great options, especially in a 13.5lb build.
Then there's UBR score shooting too! Biggest difference is caliber neutral and right now, the 22's are looking like the way to go. The 30s, 6s and now the 22s have all had their days in that game. Seems to come down to great bullets and bbls. Go figure! The more things change, the more they stay the same.