I'm surprised nobody has said the width of a crosshair is all the difference in poa/poi
Being able to get on target and aim that well after recoil is a learned art. Imo.
The sand in the bags change after each shot.adding to learning the equipment.
Every aspect has to be micro managed as much as building the perfect bullet.
Only a few get into the top10 ....not a revolving door.

I'm constantly doing an inventory on me and my equipment. More of this, less of that. So many variables ..... Whew....