Howdy,
Congrats on the purchase of a fine firearm.
During our family hunting trip to Colorado in 2000, my Dad and my youngest brother both used the same Ruger model 77 in .25-06 to kill their bucks. Dad had purchased it only a month before we left, and used factory ammo. I'm sorry, I don't recall which brand, just that it was 120 gr. bullets. Dad made the longest shot, and it was a one shot kill! My younger brother used two shots, but the deer was dead on its feet for the second. It (.25-06) seemed to work extremely well. Hope yours does for you also.
Coach