Horizontal Adjustment

Burris has rings with variable adjustment-I think it's the "signature" line. It would take some trial to get the amount of angle just right. I've used them for droop but haven't tried them for windage. The plastic inserts can be bought with varying amounts of offset.

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For those who still look for scope mounts with windage/ horizontal adjustment.

Sun Optics makes them:

http://sunopticsusa.com/rings/adjustable-airgun-rings-ring-base-combos/



A user wrote up some instruction on how to use the Sun Optics mounts right, as the design might cause some confusion:

https://www.dropbox.com/s/fmekhhelonvhtmk/Using%20Sun%20adjustable%20rings.pdf



I bought Eagle Vision adjustable mounts (only elevation/ vertical adjustment).

http://eaglevisioncam.com/

What I like about them is that they have two rather than one bolt on each scope mount that holds the adjusted rings in place. Also, they have top picatinny rails to attach more junk to my gun, and you can get their scope ring reducers (30mm to 1 inch) and a screw-in bubble level (each around $10) (ordered directly from the mfctr's website in the UK, shipping isn't too bad, very nicely packaged up).


 
I have several sets of Sportsmatch fully adjustable mounts. They seem to be stress free on the scope and they provide a solid mount which will maintain POI once locked. They require only a moderate amount of adjustment trial to set up and can be adjusted to the point that only a few clicks are needed for final zero if you want to optically or mechanically center your scope. As noted they are not cheap but if needed to correct any alignment issue they are fantastic. Have used them with no shift on a Diana 460.