It depends on a lot of things involved in the reported theft of a weapon and where the bullet from said weapon ends up. A pistol stolen at the fairgrounds at Ft. Tuthill and later used in a hold up in Flagstaff is a pretty local event, whereas a rifle missing from Managua used in a shooting in Topeka is an entirely different matter. More so if the weapon disappears from a fireplace in Edinburgh and ends up at a crime scene in Ottawa, or Mexico City.

What if the barrel is swapped out?

Ballistic fingerprinting will generally identify the weapon used and, depending upon all circumstances, could point to a suspect, but not necessarily. the only real purpose I can see for Ballistic fingerprinting is the same I see for locks on cars and homes. They keep honest folks honest. The bad guys are called bad guys for a reason.

Dan