[semi_problomatic]

Well....did you check your scope? Is the scope mounted right? Aligned? Broken? Tightened down correctly? Not torqued, twisted, or some how out of spec? what kind of scope is it?

What kind of rest were you using? Table?

Really could use more info. What was the distance, group size, were you cold bore shooting or dropping 3 quickly? What kind of pattern did it make? How were you trying to zero? Did you do 3 grouping shots and adjust? Have you tried any other kinds of ammo?

Using the information you've given I'd say swamp gas from uranus was reflecting off the scope glass and heating the air infront of your barrel causing the bullets to destabalize and tumble as they came out of the rifle. I'd suggest retuning the harmonics of your barrel with a credit card while blowing out really hard right before you shoot to remove the pocket of hot air.