I believe you'd be disappointed with the .358 STA in a 15" barrel. Too much powder for that length tube, it will have horrendous flash, report and recoil, and relatively poor velocity for all the pain. The .35 Whelen makes much more sense, as does the .358 JDJ. If it were me I'd take the JDJ cartridge unless you have to have factory ammo. None of these are pussycats to shoot with full loads.
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