Warne, Leupold and Burris state the inch pounds in the package.
On risers with a 1/2 " nut I normally see 65 inch pounds but I normally use 50 inch pounds. On base and ring screws most of the time it is 20-25 inch pounds. I use blue loctite on base screws and nothing on ring screws.
Assistant Secretary - U.S. Dry Bean Council