Unfortunately, it's completely wrong. Airline policies, TSA regulations, and US Federal Law all prohibit marking or tracking firearms in checked luggage because whatever mark, database, or whatever they use will be used by the unscrupulous to steal the checked firearms.
USC 18 922(e)
No common or contract carrier shall require or cause any label, tag, or other written notice to be placed on the outside of any package, luggage, or other container that such package, luggage, or other container contains a firearm.This includes special handling marks, computer tracking, separate bins, etc. Same reason the UPS and FedEx don't mark packages containing guns.
So, sorry. The starter pistol you declare does not decrease your chances of losing your luggage in any way, shape, or form.
The only reason that the TSA requires you to declare firearms is some moron doesn't pack something like a loaded benchrest rifle with a 6-oz trigger that blows a hole in the fuel tank when someone in seat 16A sneezes.