Is Your Scope Lying To You?

What a mil really measures in your scope

The discussion opens with a basic question: what does one mil actually equal on a rifle scope? One click on these optics is one-tenth of a mil, which corresponds to 0.3599 inches at 100 yards. A full mil at 100 yards is 3.599 inches. In theory, two different mil scopes dialed one full mil should produce the same shift on target, but the group notes that this almost never happens in practice. This leads to the idea that scopes can effectively “lie” to the shooter, and the rest of the segment sets up how to test whether a scope’s stated mil values match its real-world tracking at 100 yards.

Why vetting scope turrets matters

At Take Aim Training and Range, Clint from Classic Firearms is joined by Kaia and Josh from US Arms Co. to talk about vetting rifle scopes. Josh explains that scopes are man-made devices with inherent error, even in high-end brands like Nightforce or Schmidt & Bender. Turrets marked as quarter MOA, half MOA, or tenth mil are often assumed to be exact, but he estimates that is not true in most cases, especially with lower-end optics that have looser tolerances. The goal is to verify each tactile click incrementally. Josh stresses that a true minute of angle is 1.047 inches at 100 yards, not “about one inch,” and that ignoring this precision can create significant deviation at long range, such as at 1,760 yards, where small angular errors compound into large misses.

How scope error skews ballistic data

Josh connects turret accuracy to ballistic software and muzzle velocity estimates. Many shooters lack chronographs like LabRadar or MagnetoSpeed and rely on ballistic calculators. If a shooter assumes a muzzle velocity of 2,700 feet per second and the software calls for 14 MOA at 500 yards, they dial 14 minutes assuming the scope tracks perfectly. If the scope actually delivers only 12 minutes of elevation while indicating 14, the shooter will add more elevation to center the group and then wrongly conclude that the muzzle velocity is slower than it really is. This misinterpretation comes from trusting inaccurate turret travel. Josh emphasizes that precision shooting requires treating 1 MOA as 1.047 inches, not a rough inch, or else shooters create false problems and compound errors in their firing solutions.

Setting up the 100-yard MOA test

The team sets up a target at roughly 100 yards to vet two different optics on two rifles. Clint runs a Bergara bolt gun, the B14 Carbon Wilderness, while Kaia uses the US Arms Co. Champion chambered in 5.56. The plan is to test the scopes, not the calibers. Both shooters will aim at the bottom corners of marked squares and fire three-shot groups to establish a mean point of impact. Josh explains that they will traverse 30 minutes of angle, which equals 30 × 1.047 inches, or 31.41 inches of vertical movement at 100 yards. A small mark is placed at 31.4 inches above the initial impact point, but the shooters are told to keep aiming at the original point so they do not chase the upper dot. This setup allows the scope’s tracking to be evaluated purely by measuring the distance between the two groups.

Shooting groups with the Bergara and US Arms Champion

Kaia and Clint fire their initial three-round groups using the same bottom-corner aiming points. Kaia’s US Arms Co. Champion produces a tight group with two rounds nearly on top of each other and a third slightly to the right, forming an almost level elevation string. Josh notes that this performance matches expectations for the rifle. Clint’s Bergara B14 Carbon Wilderness also groups reasonably, around 0.6 MOA by Josh’s estimate, with one flyer disregarded. The important step is identifying the mean point of impact for each group, which becomes the reference point for measuring turret travel. Josh reminds viewers that the test is about turret tracking, not group size or caliber, and that the mean impact, not individual shots or flyers, should be used when pulling measurements.

Dialing 8.7 mils and measuring scope travel

Both rifles are equipped with scopes that adjust in 0.1 mil increments. Josh converts the planned 30 MOA traverse into mils by dividing 31.41 inches by 3.599 inches, the value of one mil at 100 yards. This yields 8.7 mils, or 87 clicks. He instructs both shooters to dial 8.7 mils of elevation while maintaining the same bottom-corner aiming points. The second groups should land roughly 31.4 inches above the first. After shooting, Kaia’s Champion again produces a tight upper group, while Clint’s second group opens up and requires an extra shot to get a clearer mean impact. With both upper groups established, Josh measures from the mean impact of the lower group to the mean impact of the upper group to determine the actual vertical travel produced by the 87 clicks.

Calculating real click value and scope error

Josh walks through the math to quantify the scope’s tracking error. For the scope on Clint’s rifle, identified as a Riton, the measured vertical distance between the lower and upper mean impacts differs from the theoretical 31.41 inches by 0.125 inches over the 8.7 mil (87-click) traverse. He divides the 0.125-inch discrepancy by 87 clicks, yielding approximately 0.0014 inches of error per click, which he rounds to about one-thousandth of an inch per click. This value represents how far each click deviates from the ideal movement at 100 yards. By knowing the actual click value instead of assuming the factory specification is perfect, shooters can better trust their dope, refine ballistic solutions, and understand how much their specific scope may be “lying” when dialing elevation for longer-range shots.