Just saw a review where .260 Rem and 6.5 Creedmore are pretty much the same except at longer distances (which most people don't do).
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Don’t get .260 Rem. Go for 6.5CM. I have nothing against 260 Rem. Effectively, they’re really not any different in performance. However in both the civilian and military markets, 6.5CM has won the war with 260 Rem. 260 Rem will become a vestigial cartridge.