The slightest disruption to a sniper rifle's aim is automatically adjusted to compensate by Oak Ridge National Laboratory's "Reticle Compensating Rifle Barrel Reference Sensor" (RCRBRS). With sniper rifles able to shoot a distance of 2 miles, the slightest angle of deflection will result in a growing margin of error the further the bullet travels. Also, as the rifle is fired, the barrel heats up also causing further error. The RCRBRS takes the guess work out of aiming, and has been proven to be 250 times more accurate than standard reticles. Lead designer, Slobodan Rajic, explains how the system works, "The optical fibers are designed to split the laser beam twice, sending one beam along the top of the rifle barrel and another light beam along the side of the barrel. Thus, we can measure both the vertical and horizontal barrel deflection." I would assume this is fine, as long as the inner bore and outer are concentric. The team also has added a laser-based bullet tracking system to give the shooter even more information about their shots.
It is scare to be a bad guy.
pic via Oak Ridge National Laboratory