Stop burning through your ammo supply trying to sight in that scope. Use The NcSTAR.300 WIN MAG Caliber Cartridge Laser Bore Sighter instead. This device will get your shots on paper taking all the frustration out of fine tuning that perfect zero. Simply install the batteries, turn the unit on, and drop it into the chamber. The factory pre-aligned laser will shine down the bore to help you get shots on target faster and safer than traditional muzzle installed devices. Constructed of hard anodized aluminum.