You are right that I don't know what you mean by saying;"is the tube long enough to get the proper adjustment"
Eye relief changes on a variable powered scope - more eye relief on low power & less eye relief on high power.
A fixed power scope has fixed eye relief.
One mounts a scope so they have a "full scope" all the way to the edge of the objective.
Eye relief is measured by that distance from ones eye to the ocular once one has a "full scope".
You may need to consider different rings to mount it "properly" - is that what you mean ?
Last edited by Sheridan; 10-20-2015 at 04:37 PM.