Dont waste your time mounting it. Simmons = Junk. They are prone to having the lenses shoot loose on rifles of no great recoil. ( a .308 in my case ) I have two buddies who have had the same experience with Simmons scopes coming apart under light to moderate recoil, so I know my problem was not a freak accident. Thought you ought to know before you waste a bunch of time with it.