Ay 6.5CM speeds, it's hard to pick a bad bullet for killing game. Pick the most accurate and run with it.
^^^^ This. ^^^^
So true. Inside of 300 yards, I'm shooting something in the 120-130gr range for lead bullets and 100-127gr for copper. My top choice would be the 120gr Nosler Ballistic Tip followed very closely by the Winchester Deer Season 125gr XP and 129gr Hornady SST. These three bullets knock the living shit out of deer and similar size game with impressive kills. If you want a mono for these ranges, the 100gr and 120gr Barnes TTSX is stellar, as is the Winchester Deer Season 125gr Copper Impact.
If you think you might be shooting farther than that, say ... out to 500 yards ... but you still want great performance in closer, then look at the Berger 135gr Classic Hunter, 140gr Hornady ELD-M, 140gr Browning Max Point, 140gr Nosler Ballistic Tip, 142gr Nosler ABLR, 143gr Hornady ELD-X and 147gr Hornady ELD-M. For a mono at these ranges, the 127gr Barnes LRX is the bee knees.
Out to 600 yards and beyond, I want one of five bullets: Hornady 140gr ELD-M, Berger 140gr VLD and Elite Hunter, Nosler 142gr ABLR , Hornady 143gr ELD-X or Hornady 147gr ELD-M. If I need this particular bullet to work well from 20 yards to over 600 yards, I would go with the Hornady bullets or the ABLR.
If I could pick only one bullet to use out of my 6.5 Creedmoor (and I do), it is the 140gr ELD-M. Kills from 0-800 yards with authority.
However, use what shoots best.