If you're shooting a light cotoured barrel the normal procedure is to shoot 3 shot groups. Heavier barrels can stand 5 shot groups without opening up the groups. If your first three shots group well then the group opens up on the 4th or 5th shot then you're having barrel heating problems. My Ruger 77 270 shoots handloads into 1" groups after some glass bedding and trigger work. Right out of the box with Remington 130 Core-Lokt's the accuracy was horrible, 3"-4" groups.