Lock Time
The brief interval between sear release and the firing pin striking the primer, where shorter timing helps a shot stay on aim.
Lock time is the delay between the moment the sear releases and the moment the firing pin actually strikes and ignites the primer. It is measured in milliseconds, set by the mass of the firing pin and the strength of its spring, and it falls inside the first instant of internal ballistics.
A short lock time matters because the rifle is never perfectly still at the break. The less time that passes between the trigger breaking and ignition, the less the muzzle can drift off the aiming point. Many precision actions use a lightened firing pin and tuned spring inside the bolt to trim lock time, helping a clean release translate into a clean shot.