I sent a 700 action and Brown Precision stock to KS Arms for a new bbl. Nothing strange. Just a 22" bbl 1:12" twist in factory sporter contour.Are you building a 358 win? What action?
I was debating between 338 and 358 for this build.
I don't think the 358 is better than the 338, but I have more history with the 358caliber and the kit was on hand for the loading. In reality, I don't think either has much to offer over a 308 load with good bullets. Gun loonyism is a sickness without regard to practical realities.
Enjoy your rifle. It's a nice one.