I need to think this one through....
If recoil is an effect of linear force, the burst of gas exerts equal force, action pushes the ball out the barrel and reaction pushes back against the bolt face...
That linear is the line parallel to the barrel and pushing back against the mass of the marker.
Most markers today are so light that that major portion of the mass is the paint in the hopper.
If the largest mass is above the line of recoil, would that make it "kick" downward?