Anyone familiar with Springfield Automatic Shotguns?

[Revan]

I have inherited a Springfield Automatic Shotgun from my grandfather. It obviously is very old, the bluing is all worn off and the forearm stock is cracked. What I do know about this shotgun is that stamped in the left side of the receiver is "Springfield Automatic Shotgun" "Springfield Arms Co", "Utica, NY USA". On the barrel close to the receiver is stamped "Proof Tested 12 GA" and the letters "SP" with a circle around them and the word "Full" below it which I assume refers to the choke. The only other markings on the shotgun are what I assume is the serial # "5939" which is stamped into the receiver right in front of the magazine ramp for loading ammo. By the age of my grandfather I believe it was probably purchased in the 30s but I'm not sure. If any old timers out there have any info on this gun please let me know. Thanks for any help.

[Synchronizor]

I believe your gun is one of many licensed variations of the Browning Auto-5 design.