How to Use Adjustable Parallax Scopes

by Jeremiah Blanchard
An accurate long-range scope needs to be free from parallax error.

An accurate long-range scope needs to be free from parallax error.

Rifle scope parallax is a term used to define image displacement as viewed through the scope. A parallax adjustment allows your scope to adjust the optics so that the cross-hairs are correctly positioned on the target as viewed through the scope. When your cross-hairs appear to move across the target, this is parallax error. Parallax adjustments are typically negligible for short-range shooting, and parallax adjustment rings are generally only available on scopes with magnification at or greater than 12X power. A simple adjustment process can be used to correct parallax error.

Set your rifle up on a shooting rest, or get into a stable shooting position.

Dial in the range to the target you're shooting on the parallax ring of your scope. All scopes will vary slightly and these range calibrations are typically numbers or hash marks with range numbers. The parallax adjustment knob is generally marked by an infinity symbol and positioned on the scope turret or on the objective bell. Turn the parallax ring to the appropriate setting.

Look through the scope and focus on your cross-hairs and the target. Shift your eye left to right and up and down slightly. Notice if the reticle appears to move across the target.

Rotate the parallax adjustment ring slightly to the right and repeat step 3. If you continue to notice the cross-hairs shifting over the target, adjust the ring slightly to the right. Keep repeating this process until you no longer notice the cross-hairs shifting.

Fire a group of four shots to test your parallax settings. If your rifle is properly sighted-in, the correct parallax settings will produce a tight shot group on the target.

Mark your scope parallax ring with a white pen line at the correct parallax adjustment for that specific distance. Move to a greater distance, reset your range dial and repeat the process so you'll know the correct parallax adjustment at different ranges.


  • Properly sight-in your scope prior to setting the parallax adjustments. This includes firing a shot group and making adjustments for windage and elevation at each specific range.


  • Never point a weapon at anything that you do not intend to shoot or kill.

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