Descrizione Scope Level 1" 30mm Scoplevel Installation Scoplevel is easy to install, just loosen ring screw one half turn, tap Scoplevel until level is centered above your vertical crosshair and snug screws. To mount a rifle scope using a Scoplevel first secure the rifle in a rifle vise and level the action with a spirit level. Then install the Scoplevel to the rifle scope per instructions above. Then install your scope onto your leveled action keeping the bubble centered as you tighten the rings. For tuning this adjustment for long range shooting try this one. Since you can verify that your vertical crosshair is plumb with the level you should be able to hit a plumb line on your target at maximum elevation. If you miss the vertical line it is caused by misalignment of the barrel and vertical crosshair