In this video, Chuck Pressburg reports frequently putting clicks on his fighting rifles to refine his zero:
https://youtu.be/kQj6JiWyslc?si=fgldvyBjkbSagz5W
Questions:
- If zero is a mechanical alignment between a rifle and its sighting system, why and how do things like clothing, shooting position, lighting conditions, gun mount, cheek weld/head position, etc. change the point of impact to where adding/removing clicks is needed?
- If zeroing is an ongoing process as Chuck says, how do you take a good cold bore shot if the point of impact changes so often?
- Bonus question: On a rifle, does resetting the trigger in recoil have any effect on accuracy or consistency compared to pinning the trigger rearward until the sights settle?