869 is a good one in the 26 Nosler and it should work well in the 6.5-300 Wby.

One can get Vulcan pull down powder much cheaper than canister powder and in my experience with the Nosler, 872 and 869 are just about interchangeable. The bonus, 872 is $55 per 8# jug. Give Jeff Bartlett a call, he knows his stuff. http://www.gibrass.com/gunpowder.html

Another powder with promise is Vv N-570, very coarse stick, double base, high energy. QL gives it high marks on performance in these big cases. It doesn't flow well thru a powder measure, stacks badly. I remove the drop tube in my Uniflow, drop a charge in a scale pan and weigh. Goes pretty fast.

DF