Hodgdon's load data has your load at approx 1840fps and that sounds about right.
I site-in my Knight to shoot 1 to 2" high at 100yds - that will keep you in the kill zone for anything bigger than a varmint from point blank out to 150yds.
Your best bet is to stay with the .451 sized bullets - typically they shoot better out of most rifles...............I think that the thinner sabots have a tighter grip on the bullet and impart the spin to the bullets better.
"Every moving thing that liveth, I give unto you as meat" (Gen 9:3)
Aim small.........miss small.
Trust God..........but keep your powder dry!