Savage Springfield Model 511

[chefgarycooks]

I just received a SxS shotgun that used to be my father's.
On one side it shows:
Springfield Model 511
Patent Pending
Savage Arms
Westfield, MASS. U.S.A.

On the other side:
A999514

Top of Barrel:
PROOF TESTED 12 GAUGE
---3 INCH CHAMBER---

I'd really appreciate any help with determining the DOM.
Any info would be Greatly appreciated!

[Mad Dog]

Made in 1972.