How do you find the age of a Remington model 4 octagon barrel with no serial number?

The Remington model 4 rolling block rifle was made between 1890-1933.If you have a model 4S military rifle,then these were made by Remington from 1913-1923.your rifle has either a 22.5in barrel,or a 24in barrel.These were chambered in .22,.25 Stevens,or 32 caliber.