Wear out a barrel or just want another caliber, just buy a prechambered barrel. A snap to change out. I saw and add today somewhere I think offering them for $339 plus tax.
Check out http://www.sharpshootersupply.com/ with go/no go gauges, a barrel wrench and clamp you can change your own barrels.
eta: heavy stainless barrels are $305 at SSS.