My only dealings with the .358 Win was a Browning BLR several years back. Due to the magazine length, I found I could not load the 200 TTSX, but the 200 TSX was fine. I also had some Remington 200 PCL, both got right at 2600 with IMR 3031. I didn't try a lot of powders and I didn't keep the rifle. At the time I had a very jeaous Mod 700 Classic in 35 Whelan AI and it wouldn't allow me to hunt with another 35! Good luck to you Pard!