The point of impact from all rifles will move as a barrel heats up. In some it is only slightly & in some much more. In very few rifles would the point of impact move so much between 1st & 2nd or 3rd to actually effect accurite hunting of big game. In high volume varmit hunting it could become a problem.

Best Wishes

With good bedding and a stress free barrelled action,the point of impact will remain very consistant from shot to shot.If the point of impact moves there is a problem with the particular gun.I have personally witnessed a case where severe bedding problems caused the point of impact to change several inches at 100 yards from the first shot to the third shot,enough to be a problem while hunting big game at longer distances if for some reason three shots or more were required.