Ring Height
How tall a set of scope rings holds the optic above the receiver, setting the scope's height over bore and ensuring the bell clears the barrel.
Ring height describes the distance from the base of the ring to the center of the scope tube, and it determines how high the optic rides over the action. The most basic requirement is mechanical clearance, since the objective bell must sit far enough above the barrel that nothing touches and the bell does not crowd the contour. A large objective therefore usually needs taller rings than a slim, low-profile optic.
Height also feeds directly into ballistics through sight height, the measured distance between the line of sight and the center of the bore that every solver needs to compute near-distance drop. Beyond the numbers, the right scope rings height lets you build a comfortable cheek weld so your eye lands naturally behind the ocular. The choice always works together with the scope base, since base thickness and ring height combine to set the final mounting height.