I wouldn't worry about getting into CNC until you had some time on a manual machine first. The kind of work that you will do in gunsmithing will more commonly be better served with a good quality manual machine. Good CNC machines have gotten cheaper; however, none of them are really all that simple to operate and require a considerable investment in time to become good with. You also need to be computer savy and have a good CAD/CAM package to really make them shine.
I still say that a good Asian lathe is a better investment than a worn out American brand.
