Here's what I can tell you for absolute certainty - it's not of a rifle that was ever cataloged which means it was either a custom order or a special run for a distributor.

As I said above, Savage only ever offered a non-adjustable ported barrel like that on the Model 16/116 FSK, and the short-action version would have only been offered with it in 1998 as that's the year the short-actions came back. In 1999 Savage came out with the adjustable AK brake and the 16/116 FSK became the 16/116FSAK from then on out.

Still, the porting you show in your first pic doesn't match Savage's pattern of ports as seen in this pic from the 1998 catalog. That leads me to believe it wasn't ported at the factory.

Click image for larger version. 

Name:	DSC02436.JPG 
Views:	59 
Size:	81.9 KB 
ID:	6392