The eye relief problem could be a simple as the mounting surfaces (distance of the flats of the tube between the turrets and lenses) are not the same on both scopes thus not allowing you to move the Nikon as far to the rear on the rifle as you can the Burris.

The Burris has nearly a full inch more mounting surface available on the main tube between the turrets and the lenses. In other words the main tube is longer on the Burris than it is on the Nikon.

The nikon has 2.05" mounting surface available vs. 2.5" available on the Burris for the front ring.

The Nikon has 2.03" mounting surface available vs. 2.5" available on the Burris for the rear ring.

So, the Burris is able to be mounted at least a half inch farther to the rear than the Nikon. You're going to have to get extension rings or a different base to get the Nikon to the same position.



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