I had 400 Barnes TSX 500 grainers showed up as a gift from wifey for my .458 Win Mag.

Here's what the data says
Bullet Weight: 500 gr Case Trim Length: 2.490" S.D. 0.341
Bullet Style: Barnes Banded Solid
H4198 49.0 Grains 1857 55.5 Grains 1999 93 http://www.barnesbullets.com/i...chesterMagnumWeb.pdf

Here's what the Hodgden data reads and the load I want to try.
510 Grain Winchester Spire Point
IMR 4198 44.5 grains 1645 52,400 CUP

Am I in the safety zone substituting bullet styles? I have in my inventory 4 IMR 4198's and 6 H4198's 8 pnders that I would like to use.

I don't know, but I hope you are very young if you plan to shoot up 80 pounds of 4198 from a .458 Mag.