How to "Box Track" a Scope
by Al Jole
In the world of shooting, scopes are used in various ways. Some people zero the scope at a given distance and then simply hold over or use Kentucky windage on their shots to account for different ranges and wind conditions, putting their crosshairs above or to the left or right of the intended target. Others use scopes with adjustable "target turrets" to allow them to dial in the range and windage, so they can center the crosshairs on the target in any situation.
These types of adjustable scopes can be had for a wide array of costs, but in any case, one must be certain of the ability of the scope to "track" or adjust correctly and repeatedly in any direction; and then to return to zero when asked. To do this, many use a technique called "tracking the box".
This is only useful on a scope that one intends to adjust for range and windage, to ensure that it actually adjusts correctly, and that it returns to your base zero after being adjusted all over the place. If you just zero and then hold over or use Kentucky windage on your shots, it's not really a useful test.
To do the test, you will need a good solid rest, a gun with a solidly mounted scope, and 6 bullets that you know to be consistent in your gun.
Lock the gun down tight in the rest, or get yourself as solid as you can in a supported shooting position. The better you can lock the gun in, the better the test should be.
Shoot one shot at the bullseye of target.
Adjust scope "up" to some known adjustment, such as 20 clicks for 5 inches, then right 20 clicks, aim at the bullseye, and shoot a second shot, aimed at the bullseye. Don't try to adjust your aim point, don't compensate for anything, just aim at the bull exactly as in the first shot, and shoot it.
Adjust down 40 clicks, shoot at the bull.
Adjust 40 left, shoot once again, aimed at bullseye.
Adjust 40 up, shoot at bull.
Adjust 20 right and 20 down, shoot at bull.
You have to aim at exactly the same spot, no matter where the bullets hit.
If you want to REALLY test the scope, use more clicks, assuming there is enough adjustment left in any plane to allow for it.
If your scope is working properly, the last shot should be exactly on the first hole, and each other hole should make a nice square with each hole the same distance from the center, and from each other horizontally and vertically, with both diagonals also equal to each other. A box, you see.
If you didn't get the nice perfect box, it may be your shooting technique, so don't toss your scope away yet. But if you CAN shoot nice tight groups, the scope should be able to make a nice square box. If it can't, it may be loose tolerances in the gearing, or some other issue inside the scope; some companies will fix that on warranty, some won't; this is part of the reason for the cost differences.
If you can shoot well, but your scope doesn't track well, you will need to decide if it is close enough for you, or if you want to keep the scope and just hold over instead of adjusting it, or get rid of it and try another.