when you say "H4831" do you mean IMR4831? That is a powder load from the reloading book I have. I don't really feel comfortable using a powder that is not listed in a book.
The powders listed under the 160 grain bullet options are IMR4064, IMR4320, IMR4350, AA3100, RL19(my neighbor has this powder), RL22, IMR4831, Vihnt N165 (most accurate powder with their test rifle), IMR7828, and H870.
Keep you initial tuning simple.
Get a good reloading manual and read it.
Start with the recommended minimum power charge, and work up in 1/2 grain increments until you either experience pressure signs, or reach the max load. Shoot groups. If you get some good results, load up some more of the load that produced the smallest groups and see if you can reproduce that result.
For powder, I'd start with H4831, It's and old classic that's worked well in 7mm Rem Mags for me in the past. [/quote]
