From Vortex: The Vortex TMT (Trajectory Matched Turret) elevation cap is not just a simple BDC cap, it is truly custom-matched to your favorite rifle and load. For maximum speed when adjusting for accurate long range bullet drop, nothing beats dialing a yardage-marked elevation turret cap. No calculations are necessary—simply range your target and dial the turret to the matching range. Building a TMT elevation cap is easy and does not require the use of specialized equipment such as a chronometer. Has anyone used one on there scope, how did it work for you?