between the stock and the barrel
It will be marked on the receiver/barrel.
Try the receiver, barrel, forend
Look on 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.
Unable to answer as asked. Is it already a shotgun or will it be built from a virgin receiver?
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.
Check the receiver and barrel
Where will be marked on the barrel/receiver.
Check the receiver sides and bottom and the barrel
Check the receiver and bottom of the barrel
Look on bottom of receiver and barrel