I am building it partially to have something different, but it is going to be used for hunting. Honestly, nothing big enough to really need the caliber chosen, but I already have one in .308 so why not lol. I will primarily use it for black bear here in Michigan and I might throw it in on an elk hunt in Colorado we're taking next fall but I'm primarily using my my 300 win mag. Funny you mentioned the .358 win, that is my backup plan if I couldn't put together a magnum AR10.