First, in MOST of the US, there is no requirement for registration of ordinary rifles, shotguns, or handguns.
Second, while in the US it is illegal to REMOVE a serial number, or to possess a gun that has had the serial number removed or made unreadable- not all guns HAD a serial number.
Prior to the 1968 Gun Control Act, no Federal law required that rifles or shotguns have a serial number, and there are large numbers of those guns that have never had a serial number- and possession of those is perfectly legal.
For recordkeeping on those guns, the serial number is recorded as NSN- No Serial Number. I collect older 22 rifles, and have about 30 that were made prior to 1968. Only 2 of the 30 have serial numbers.
First, I think you mean register. In MOST of the US, there is no requirement to register ordinary firearms. Now, about the serial number- it is unlawful to REMOVE a serial number, or to possess a gun that has had the SN removed. However, there are guns that do not HAVE a serial number, and they are legal. Rifles and shotguns made prior to 1968 were not required to have serial number. Those guns are listed as NSN- No Serial Number- on paperwork that asks for a serial number.
As long as the serial number is on the gun and can be ran, you should be able to register it. If the number is bad, the police may confiscate it.
Yes it is illegal to own a gun that does not have a serial number. It is also illegal to remove the serial number off a gun.
Depends. In MOST of the US, there is no requirement or means to register an ordinary handgun. Depends on the law where YOU live- and you did not share that with us.
With just the serial number, nothing.
It would be almost impossible to identify a gun just by its serial number.
Just by the serial number, no.
Impossible to answer. A serial number is not unique to only one gun in the world.
Impossible to date a gun with just the serial number and no other informaiton.
The serial number is on the frame.
Gun Registration...
You find a published list of serial numbers for the maker.