Please forgive my lack of knowledge on this matter, but I guess I just need somebody to explain it to me. I'd like to pick up a Savage in .223 for my varmint hunting needs, but would also like to have a custom barrel made in .300 whisper. Since it's common to use the same action and magazine for the whisper, why can't I just have the extra barrel made and just swap them out when I decide to go from varmints to big game. Thanks in advance, people.