I finally finished tiling the basement, concrete work and spring food plotting and had time to go to the range to chronograph Rl17 loads I made for the 358WSM. The results of the experiment were as follows:
Rl17 75gr...Horn 200gr SP...3010fps ave for 5 shots.
Rl17 75 gr...225AB...2978fps ave for 5 shots.
fire-formed 300WSM brass
Labradar used
Win M70, Hart 22 inch #3, 1-12, "358 X 300 WSM .389ND" nicely stamped on the barrel
These loads were found published in my internet search of 358WSM/Sambar. I think in an article by Bryce Towsley but I could not find it again to reference here. Sorry.
I am no expert but know velocity equals pressure and these velocities seem fast for a case of this volume. However, bolt lift and extraction were without hesitation and the primers were still rounded similar max book loads I use in my 300 and 270 WSM. The primer pockets were starting to loosen though, this being the third or fourth reloading of differing loads. One more and the brass is probably done.
If, I were to hunt this rifle, I would load the 225 AB to 2800fps and be happy. Its niche for me is a 7 1/2 lb. backpack rifle for black bears-light,handy and some extra horsepower. That it is. But I've had it for 16 years and rarely shoot it choosing a 358 Win, 9.3x62, 375 B&M or H&H for my bear hunting so it is a safe queen.
