Q: "What is the go to Hodgdon or IMR powder for it? Those seem to be the only brands I can sort of reliably find."
A: Hodgdon from faster to slower below: H4198 H322 Benchmark H335 (ball) H4895 Varget
Except for H335, those are all extruded "EXTREME" powders of good Thermo-Ballistic-Independence, Benchmark maybe the best of all in regards to TBI. H335 ain't bad in any way, however.
AA-2230 and AA-2460 fall right between H335 and H4895. They are supposed to be formulated for improved TBI in lots since 2016. I think AA-2230 is made from AA-2460 with half of the balls flattened to make it burn a little faster and pack into a smaller space.
Anything good in a .223/5.56 is good in the .458 WinMag, so the black rifle fad has been a boon to the .458 WinMag. From AA-5744 to CFE 223, for light to heavy bullets.
If I had to pick one powder it would be H4895. You can use it at 60% of a maximum load and requires no filler, for all sorts of light loads. You can also use it at 110% compressed after drop tube and get well over 2600 fps with a 400-grainer:
You use the maximum Woodleigh manual load for the .458 Lott with 400-gr PPSN: 87 grains COMPRESSED H4895
Crimp the bullet in the Woodleigh cannelure for the .458 Lott. Roll another cannelure onto the Woodleigh bullet 0.3" below the factory cannelure, using a CH4D Cann-Tool. Then load the .458 Lott and the .458 WM+ with same powder and same degree of compression to same COL: 3.425" The Woodleigh 400-gr PPSN has a short nose projection of only 0.625" in the .458 Lott load with seating depth of 0.530". In the .458 WM+ load, the nose projection is 0.925" and seating depth is only 0.230" with this stubby cup & core bullet. This is just a stunt to prove a point. I did it.
Woodleigh manual result for a .458 Lott with unspecified barrel length, probably 24" = 2570 fps My result for .458 WM+ load in 25" Shilen barrel with SAAMI .458 WinMag chamber = 2627 fps MV
Whooped the .458 Lott again.
Ron aka "Rip" for Riflecrank Internationale Permanente NRA Life Benefactor and Beneficiary .458 Winchester Magnum, Magnanimous in Victory THE WALKING DEAD does so remind me of Democrap voters. Donkeypox.
