Turret Tracking
Also: Tracking
How faithfully a scope's actual point-of-impact movement matches the values dialed on its turrets, the core measure of a scope's mechanical honesty.
Tracking describes whether the reticle, and therefore the impact, moves exactly the amount the turret markings promise. When you dial ten units of elevation, a scope that tracks perfectly raises the point of impact by precisely ten units, and dialing them back returns you to the original aim. Without trustworthy tracking, every correction you dial becomes a guess, and the careful drop data you collected loses its value.
Tracking errors usually show up as a consistent percentage off, so a scope might move only ninety-seven units when you dial one hundred. Shooters confirm tracking with controlled procedures such as the box-test, which checks both movement and return, and the tall-target-test, which measures the true click value over a long vertical run. Verifying tracking before trusting a scope at distance is standard practice in precision shooting.