RE: Weatherby should adopt the .220 Swift
I don't think Weatherby chambering the 220 swift would do much for its popularity, unless they opted to do so at the expense of the 22-250. Even then, that probably wouldn't do much. The rest of the manufacturers would need todo the same.
I don't quite understand why the swift isn't more popular already. Seems to do what the 204 and 22-250 do only better, IMO.
The 223 is so inexpensive and widely available that I would guess it will always be the most popular. I can't see any of the other centerfire 'varmint rounds'ever really competing with the 223, sales-wise.