We were in the X and 10 ring. All other teams were high in the 8 and 7 ring. We believe that re-zeroing in the new condition will only prove the mechanical soundness of the weapon. Carlos Hathcock admitted that his 2000 yard shot in Vietnam with the .50 cal. Admittedly a great deal of luck was involved also.
All courses mention correcting for environmental conditions.
Because of a lack of knowledge of the subject, it is usually paid lip service. The data that is put out is usually hand me down information from open sources that is frequently inaccurate. This subject receives little more than a slight mention at most schools. It is accepted that combat sniping ranges all occur at ranges that the bullet will remain in supersonic flight. This is generally accepted.