stock measurements are important regarding target rifle stocks if competing in ibs or nbrsa registered matches. the target rifle stocks must meet certain dimensional and configuration criteria according to the class of competition engaged in. stock dimensioning is especially important with shotguns, where the typical front-bead-only sight requires a consistent positioning of the shooter's eye over the center of the barrel for good accuracy. when having a stock custom built or bent to fit, there are a number of measurements that are important.