I was using Varget in the 22/250 as it worked out the best. Tough call since the barrel is basically shot out. When I seat the bullet to touch the lands it barely has a toe hold in the case. The former powder was 4064.
6mm Creed with the 65 grain V-MAX, devastating round, not more than a 243 but they just hit coyote hard far off. That was with 4064. R19 is the powder for the 105's.
I have an opportunity to pick up a keg of 4166, Think I'll go for it.