Mine is a 12 gauge pump. Chambered for 3" shell.
Springfield was a trade name used by Stevens/Savage c. 1920-1945. No relationship to the current Springfield Inc or the US Springfield Armory. What you have is a Savage Model 720 built under license from FN (Browning) They where also made by Remington with the Model 11 designation.
I've got a Springfield 12 gauge double in for repair and it appears to be from studying the Jack Frost catalog to be a Stevens 315. Go to e-gunspart.com and they have a schematic listed for $.99.
These are valued between 125-180 dollars,based on overall condition of your shotgun.
About $100 in very good condition.
A Savage model 24 -3030- 12 gauge in good condition is valued at $500. It is a rifle over shotgun combo.
The Savage model 220 was available in 12 gauge,16 gauge,20gauge,28gauge,and 410 gauge chambered barrels,with a barrel length of between 26 inches-32 inches.
I'd bet that is 311A instead of 3114. Savage/Stevens re-named the Model 5100 as the 311 series about 1942 and discontinued the Springfield name in 1948. Depending on condition, it should be worth between $150 and $250.
The Savage/Stevens model 944 was made from 1936-1942.There were 1,500 made during this time span.The value would be hard to establish without a more detailed description of your shotguns overall condition.