Yep and they are Magnum Contour (Heavy)1 in 14" Twist (good all around Twist) and 24" long (longer than needed for the .358 Winchester).
A couple of reasons why I like others have said that if you have a rifle or are willing to find a rifle to have JESS Re Bore then you will have a lighter and probably a handier rifle and save some funds as well. On a side note JESS can also cut some length off of your barrel if you so should wish for a nominal fee.