wow ! something doesn't sound right, are you sure everything is tightened and aligned properly? I am concerned, something is way off, not even sure how your groups open up that much in a 100 yards…. .5" at 100 to 5-6"at 200?? Even the light weight bullets should hold grouping better than that…I have no answer but someone here will.. sit tight brother, we'll get this fixed… Not sure, but a stab in the dark,what kind of glass are you using? Are you increasing magnification as you increase range? I only ask because I wonder if the reticle is loose in your scope? Stab in the dark!