Even LEO's that are involved in a shooting have their gun held as part of the case evidence. If you fire your gun and don't hit anybody, it will most likely be taken for evidence. If your gun goes to a state lab for testing it will most likely have a lab number etched on the gun. The way it is and a reason not to carry a gun that is very valuable or irreplaceable. On the other hand, if your gun saved your life, it did it's job and is worth the cost of replacement.