Try contacting Savage directly, they would be better advised to answer you than we could.
I would have to assume that you have a semi-auto shotgun.If your shotgun has a slight hump to the back of the reciever then it was a shotgun made with a browning patent and would have to be listed on the gun along with the royaltys paid to his patent.
This Shotgun was made by Stevens their model. 520. Made from 1930's to 1950'S Although the shotgun was Browning patent marked, it was not made by Browning.
Gun Digest.
Stevens 520 pump
The Stevens Model 520 was built on a Browning patent and so marked. Stevens also built the gun for Sears before World War II under the 'Ranger' tradename, so if you have a slide-action shotgun marked 'Ranger' and 'Browning Patent' then that is what you have.
You need to identify the make and model of the shotgun. Dozens of different makes of guns show a browning patent on the barrel. Recheck and re-ask the question - Thank you
I can tell you that with the Western Field name, it's not a Browning product. This was a trade name used by Montgomery Ward. It may be marked with a Browning patent, but was probably made by Stevens/Savage.
It is a Stevens shotgun, based on a Browning patent. Inexpensive.
To locate a manual for your shotgun,you must provide the model number for your shotgun first.All shotguns made for Montgomery Wards(Western Field) were made by other firearms manufactures for Montgomery Wards to include Savage,Stevens,Mossberg,Noble and more.
No sn data in the public domain.
1930's.
The first Browning Automatic Shotgun patent was filed for on May 6, 1899, but not granted until June 16 1903. This was the first patent filed, but the last of four patents to be granted that had to do with the final configuration of what we know as the A5. auto5man