MSP Ret,
Well.......I hope I can furnish you a better idea of the model and date of mfg.
* Because the s/n is post 1 million it can be safely said your rifle was made after 1960.
1) In 1960, Savage Arms Corp. factory moved frpm Chicopee Falls, MA to Westfield MA.
New models of the 99 were added: 99E economy carbine, and 99DL deluxe rifle (99DL with new improved trigger sear, and sliding thumb safety on top tang).
2) In 1963, Savage Arms Corp. becomes a division of the Emhart Corp., involved in hardware, glass making machinery, packaging machinery, and refrigeration equipment.
3) In 1965, new models 99 added. 99C - the first major change to the original 1899 design; added a detachable box magazine with a push-release button on receiver right-hand side.
99DE and 99PE - deluxe engraved presentation models.
Impressed checkering added to all models at this time (except PE).
Generally speaking the post 1 million numbers are considered an indication of a down-turn in quality, but you say you have a rotary magazine (which are considered to be a BIG plus over the clip model), and cut checkering as well. You have a .308 caliber which Savage offered in twelve models: 99R, RS, EG, F, DL, E, C, DE, PE, 95, A, CD.....later only in the 99-C.
Hint....you might find a model stamped on the barrel, under the forearm wood.
One last thing: The address on the STYLE 9 made from 1946- 1960 were 438,000 - 1,094,000 "SAVAGE ARMS CORPORATION
CHICOPEE FALLS, MASS. U.S.A."
STYLE 10
1,094,000 - 1960 " SAVAGE ARMS
WESTFIELD MASS. U.S.A."
Jim