Ballistically (and dimensionally, except for neck length), there is very little difference between the .300 Savage and the .308 Win, and as the .300 Savage cartridge is rapidly moving into semi-obsolete status, it's not likely that the new Savage AR in .300S would attract much of a following if for no other reason than limited ammunition availability. However, it certainly wouldn't be difficult or costly for Savage to offer it in .300 Savage to test the waters.