My favorite most accurate load in my .358 BLR is....
Win .358 brass
Fed 210 LR primer
47gr of IMR 3031
Hornady 200gr SP.
this load shoots a 3 shot group into a single jagged hole at 75yrds.
My next in line would be...
Win .358 brass
Fed 210 LR primer
47gr of IMR 3031
Speer 220gr flat nose
this load shoots 3 shot clover leaf group at 75yrds.
I have tried W748, and IMR4895 with these bullets as well,...these powders shot good groups as well but not as tight as 3031.
Congratulations on your purchase of a very nice, great little, excellent handling, fast pointing, excellent fitting, smooth action, rapid repeating, proud to own rifle, LOL..... Incase you didn't guess,...I love my .358 BLR.
The deer, bear, elk, moose, what ever in your neck of the woods are in real jeopardy, lol. Have fun and good luck.