A 412.
Many moons ago, Valmet made the Savage 2400's which "did" use Sako dovetail rings, but then Valmet designed the new 412 system... The VERY early "experimental" 412 bbls did have the Sako dovetail on them, but VERY few made it to the gen. public and although possible, i doubt you have one of those. The 412's that went to the public had a new designed system that is a "detach" base that the rings are mounted to.. It comes as in this pict...

This system is "excellent" and allows you to take the scope off and reinstall it without having to re sight the bbl... I've had mine on and off a zillion times, and it all works as advertised!!
They are all steel and built to last!!
DM