Many early ones may not have a serial number. If they do, it will most likely be on the side of the receiver. There is a small chance it will be inside, after you remove the barrel.
What year was riverside, 12 gauge, single shot ,model 548 made
Check the barrel and receiver
Try the receiver, barrel, forend
Check the receiver and barrel
look on the breach, barrel.
Please include the model number of your Winchester shotgun to get a correct answer to your question along with the serial number.
With the serial number that you provided,your Ithaca double barrel shotgun with the damascus barrels was produced in the year 1900.
You may have to break the shotgun down in to the barrel section and the receiver section first.Look under the barrel section on the flat just ahead of the lug for the serial number.
== == "Riverside" was a brand model shotgun produced by the J. Stevens Co. (which was bought out by Savage in 1920) - These were utility grade double barrel shotguns manufactured between 1877 and 1988. If the serial number is prefixed with a letter it was manufactured after 1949. If there is no letter, it was manufactured prior to that. Thats the best I can do.
when did spring make 12g single barrel shotgun serial number 30368
next to the barrel
Check the frame and barrel