Yuppers,,, we had a fellow at our range that had groups all over the map,,, we checked everything on the rifle to make sure it was good...
I lent him my solid shooting bags that deffinatly tightened up the group,,, then we took the time to adjust the parallax to shrink the group some more...
Next time he came to the range he was shooting bug holes with his lite weigth 308...
Of course parallax really plays a role when distance gets involved...
Yo Yo Yo