Rifleman Q&A: Centering Crosshairs

by
posted on July 9, 2021
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
Crosshairs
Counting clicks is not always reliable, because some of the scopes are deliberately designed to provide more upward adjustment than down travel.

Q. Before mounting a scope, I like to make sure the crosshairs are centered. To find the optical center, I heard that you could take a mirror and place the scope on top of it and look into the scope. If you see two crosshairs, then it is not centered. Can you better explain this procedure and tell if this is the correct way to find true optical center?

A. The mirror procedure you described for centering a scope reticle does not work very well because of the difficulty of seeing the reticle with little or no light entering the objective lens. Counting clicks is not always reliable, either, because some of the scopes are deliberately designed to provide more upward adjustment than down travel, while others may simply escape from the factory with asymmetric elevation and/or windage travel in the adjustment mechanism.

I learned the best way to center scope reticles from Bill Ackerman of Optical Services Co. With that procedure you will need either a simple V-block fixture for unmounted scopes, or a rifle-holding vise to immobilize a rifle on which a scope is already mounted. In the latter case, loosen the rings just enough to permit rotating the scope easily, but not so much that the scope wobbles while doing so.

Set up the rifle/scope or the V-block device so the scope reticle is aimed at a reasonably distant (100 yds. or so) target or easily distinguished terrain feature. While viewing through the scope, rotate it 180 degrees so the elevation turret is beneath the tube. If the reticle is off center, you will see it slew to a different aiming point from the one you established initially. If that happens, use the elevation and windage adjustments to shift the dot or crosshair one-half of the distance from its new position in the direction of the first aiming point. Now, while viewing through the scope again, rotate it back 180 degrees to its original orientation, with the elevation turret pointing up. If the aiming point of the reticle drifts from the prior (second) reference point on the target, once more adjust the elevation and windage controls to move the reticle one-half the distance from its current (third) position. At that point, the scope reticle should be well centered for all practical purposes. Donユt forget to retighten the scope rings if applicable.

—Hugh Birnbaum


This “Questions & Answers” was featured in the September 2004 issue of American Rifleman. At time of publication, "Questions & Answers" was compiled by Staff, Ballistics Editor William C. Davis, Jr., and Contributing Editors: David Andrews, Hugh C. Birnbaum, Bruce N. Canfield, O. Reid Coffield, Charles Q. Cutshaw, Charles M. Fagg, Angus Laidlaw, Evan P. Marshall, Charles E. Petty, Robert B. Pomeranz, O.D., Jon R. Sundra, Jim Supica, A.W.F. Taylerson, John M. Taylor and John Treakle.

To subscribe to the magazine, visit NRA membership page here and select American Rifleman as your member magazine.

Latest

springfield armory kuna
springfield armory kuna

Springfield Kuna: A PDW For The Masses

Small, yet fierce, the namesake of Springfield Armory’s latest large-format pistol is a revered forest dweller in the land of its Croatian manufacturing partner, HS Produkt. The new Kuna is poised to be just as welcome in America.

The Armed Citizen® June 30, 2025

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

Book Review: Clockwork Basilisk: The Early Revolvers Of Elisha Collier & Artemas Wheeler

The result of a decade of research, Clockwork Basilisk is a comprehensive, two-volume history of the rare revolvers that preceded the development of the well-known Colt guns of the 1830s.

Preview: 1791 Gunleather Cobra Gun Belt 01

Employing the same rugged and rigid 0.25"-thick American steerhide as 1791 Gunleather’s original Gun Belt 01, the new Cobra Gun Belt 01 offers enhanced ease of use by taking advantage of a high-strength Cobra quick-latch/release buckle.

NRA CEO Hamlin and President Bachenberg Hold First Virtual Townhall

In the interests of transparency, NRA CEO and EVP Doug Hamlin and NRA President Bill Bachenberg held a live Townhall event, where both answered direct questions from NRA members.

Benelli Adds New 28-Gauge Models to Super Black Eagle 3 Line

Benelli initially introduced the 28-ga. chambering to its Super Black Eagle 3 line in 2022, but this year, the company added three new models tailored specifically to hunters.

Interests



Get the best of American Rifleman delivered to your inbox.