How do you trace firearms serial numbers?

If you're referring to the United States, the most basic answer is, you can't.

The serial number should be engraved on the weapon, usually on the barrel.

It could be in a number of places. For most rifles, it tends to be on the receiver, while semi-auto pistols tend to have it on the slide. On some older rifles and shotguns, you may have to remove the...

It depends on what you mean. You can obtain some information about the gun itself, such as manufature date by the serial number, but as far as "registration" or finding previous owners or anything...

Pretty much from the first time someone wanted to know how many were being produced<><>And when folks needed to account for WHO had WHICH gun, when they were same model and make. Serial...