Without the name of the maker and detailed descriptions of the weapons, the question can't be answered.
No. Serial numbers were not required until 1968 on rifles. Most have a Sears model number that is mistaken for a serial number
Winchester Rifles do not have letters in their serial numbers. The year of manufacture for serial number 45081 is 1941. Source: http://armscollectors.com/sn/winlookup.php
A number of rifles did not have serial numbers prior to 1968. but, that has changed.
This may sound strange, but if it never HAD a serial number, not a problem. Serial numbers were not required by law on rifles and shotguns until 1968. I have about 20 rifles made in the 1940s and 50s that do not have serial numbers. REMOVING a serial number is a serious crime, however.
Serial numbers were not required on rifles and shotguns until 1968.
There isn't any. Mossberg did not put serial numbers on their rifles until 1968
Until the 1968 Gun Control Act, no Federal law in the US required serial numbers on rifles or shotguns. For other readers- yes, it is perfectly legal to own a rifle or shotgun that has never HAD a serial number. It is HIGHLY illegal to REMOVE a serial number.
Not certain I understand what you are asking. If your gun HAS a serial number, it should be stamped into the metal of the receiver (frame). In the US, serial numbers were not required by law on rifles and shotguns until 1968. Many older rifles and shotguns- especially .22 rifles, have never had a serial number, and they are perfectly legal,
It could be because sequential serial numbers would have allowed someone to collect a sample of rifles and then estimate the total number produced.
There are 17 letters and numbers in the serial to the Suzuki LT80, it is considered a VIN number.
I am sure the first rifles made using black powder did not have a serial number engraved. Antique rifles without a serial number do exist. I am however unsure what the law state about collector pieces. Logically one can not force a serial number onto a piece that originally was made without one.
I don't know if all High Standard A-100 rifles (semi-auto, .22LR caliber) had serial numbers. Gun companies didn't have to use serial numbers until 1968, and a lot of inexpensive .22 rifles and shotguns didn't have any serial numbers back then.