Has anyone tried H4198 in the 6x45? It has a burn rate just ahead of VN133. I'm thinking of trying it with 55gr nosler BT or lead free BT. Any ideas?

I am using an 18" mid length BHW barrel.

My best loads to date are:

27.0 gr Benchmark, Win NT brass, 55 gr Nosler lead free, 3/4" ( 3 shot/100 yds) and +/- 2990 fps. Compressed load

28.4 gr Exterminator, LC brass (or ICC), 55 gr Nosler BT, 1/2"-1" (3 shot/100 yds), +/-3144 fps. Not as consistent accuracy as I would like.