260 is an awesome cal and you have your choice of brass...with the 6.5CM your stuck with hornady brass...as far as which is a better long range caliber its pretty much a wash...personally id take a 260 over a 6.5CM any day because of brass...lapua,nosler,Winchester,remington in 243(neck size up to 6.5),260 outta the box or 308(neck down and neck turn) take your pick.
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