I like the Varmageddon but much prefer the 55gr BT, as for powder I have one rifle that loves Vargay with either bullet. as mentioned H4895 is a good choice to test with, gotta disagree with Swifty on H335. would never use this power in a 22-250 as it is the most temp sensitive powder I've ever used and a bit too fast of a burn rate also. some of my other fav's are VVN140-150 but by far the first powder I try with your combo is W760/H414.........
You say you have Nosler and Lapua brass, you will have to tweak your load a bit. the Nosler brass is softer than the Lapua so you might have to back off a half grain or so
