Different POI with Different Shooter?

[MMACFIVE]

I sighted in my friends gun and when he shoots it he is about an MOA or more higher then I am. Both off the bench and prone with a bipod.

What are some of the cause of this? I know the tighter or more I lean into a gun the higher I shoot.

[Chef]

 

Cheek weld differences will have an impact.

[lancetkenyon]

Recoil management, cheek weld, pressure/loading into the rifle (actually been proven to change velocity slightly too), eye differences for diopter and parallax changes, sympathetic grip/pressure/movement of the shooting hand, shoulder placement of stock, body position.