These are some pix of my Springfield M1A with a Smith Enterprise mount, Weaver rings and a Shepherd scope.This is a fairly expensive steel scope mount. It mounts to the receiver in three places, all adjustable. I tried the much less expensive aluminum mount but, while nicely-made, it could not stand up to the pounding it took from the recoil. Notice the misspelling of the word "PATTERNS":
This picture shows how the scope mount has a U-shaped channel down the center. This channel allows the iron sights to be used without removing the mount from the gun. The scope, though, is another matter, as the huge bell of the front optic completely blocks the iron sight. Get some taller rings, though, and you're in business!