Firearms are assigned serial numbers for the purpose of identification. When a gun is purchased, the buyer registers it with the proper authorities who record the owner’s name into a database along with the weapon’s serial number. If needed, law enforcement officials can then trace the number back to the original owner, or the owner to the gun, much like a driver’s license number can be traced to a driver.
Serial numbers are stamped into a weapon’s metal frame with extremely hard dies that push the numbers deeply into the steel.
Criminals, in an an attempt to be “untraceable,” often try to remove the serial numbers. The most common method of removing the numbers is to grind them away using, well, a grinder.
A firearm with a missing serial number is impossible to trace to its owner, right? Well, maybe not. Investigators do enjoy a bit of success at restoring serial numbers. You see, when the original number-stamping was performed, it was done with such force that the metal beneath the numbers is placed under permanent stress.
Number restoration kit – Sirchie Fingerprint Laboratories
Therefore, when the proper restoration agent is applied to the spot where the serial numbers once were, the strained particles/crystals dissolve at a much quicker rate than the undamaged metal.
Restoration gel for steel (also available for copper and aluminum).
And when those particles dissolve they leave slight indentations. And what do those indentations look like? You guessed it…the original serial numbers.
Restoration reagents for plastics – Sirchie image
Okay, suppose the serial number is/was etched into the plastic body of a TV set. Well, there’s a reagent for restoring those numbers, too.
Now that you’ve restored all the numbers, a quick check into the database leads you to the bad guy. Then it’s a simple matter of locating the weasel, handcuffing him (using cuffs with deeply imprinted serial numbers), and taking him for a ride in a patrol car.
By the way, even that patrol car (yours, too) is equipped with numerous serial numbers—engine block, VIN number (vehicle identification number) on the dash, radio serial numbers, auto part numbers, VIN number stamped on the chassis, and many, many more.
VIN number is often located in the defrost vent in the driver’s side windshield.
Other VIN locations.
* Police officers often use VIN numbers to locate owners of abandoned and stolen cars.