Many manufacturers used the same receiver for different gauges. H&R, for example, used the same receiver in the Topper series for everything from .410 through 12ga. sales@countrygunsmith.net
between the stock and the barrel
By designer are you asking what Model it is? If so, the Model can be determined by the serial number, which is located on the barrel flats and the forend. You have to take the barrel off the receiver to see them.
Check the barrel and receiver
Try the receiver, barrel, forend
It will be marked on the receiver/barrel.
Check the receiver and barrel
If you have a Model 30 pump shotgun, the barrel is not intended to be removed by the user. To do so requires specialized tools such as a receiver block and a barrel wrench. You can clean and lube the shotgun with the barrel attached to the receiver. Contact Savage Arms Customer Service and get an owner's manual for your shotgun.
Look on the receiver and barrel.
Unable to answer as asked. Is it already a shotgun or will it be built from a virgin receiver?
CHeck the barrel and receiver.
It will be marked on the receiver/barrel where it was made.
The receiver is the largest metal piece of the shotgun, in other words, the frame of the shotgun. All the other parts, such as barrel, stock, bolt, etc- attach to the receiver. With modern firearms, the receiver will be marked with the serial number. Legally, the receiver IS the firearm- all other parts are simply parts.