I have two '94 .30-30s. One with a 20" barrel and one with a 26" barrel. Both have an octagonal barrel and a saddle ring. They will be shot. They will not be shot a lot."heirloom rifle" in a cartridge conversation = Rifle that isn't going to be shot enough to need a new barrel.
I'd have a hard time thinking of a rifle I'd want that I would plan on shooting so little over 30 years that it still has the same barrel on it.