Originally Posted by
J.Baker
By law, any firearm manufactured or imported for sale in the United States is to have a makers stamp on it to include the name of the maker and their location. Can't recall if that's part of the National Firearms Act of 1933 or the Gun Control Act of 1968, but it's one or the other.
Most gunsmiths just have a cheap set of individual stamping dies to mark their barrels with the chambering and twist, so when you see the individual numbers not in a nice straight line or evenly spaced it's usually a pretty clear indication it's either an aftermarket barrel or a retrofitted/reworked barrel that originated on some other gun. The latter is rarely seen on Savage's due to the larger shank diameter of their barrels and lack of a shoulder for headspacing.