worst scope II

well the tasco on my son's .204 went tits up, the tasco on mine is still working great for now! ordered him a bushnell 6-24x40 and see if it's a better product than the tasco! At the range mine was printing 1/2 moa at 100 yds, his wouldn't do anything consistant except for being constantly to the right, two shots would be one inch apart third shot would go high about six inches, adjusted to compensate and first two would hit close together then third would be high and to the right every single time, got out the tools and checked for lose rings they were solid, took it home removed the scope and checked the base it was solid. only thing i can figure is the internal parts let go. lets see if the bushnell is better, last range trip his was printing under 1/2 moa, I know the .204 doesn't recoil much but the vibration has got to be horrendous.