I'm trying to remember. You want to set the screw so the piston doesn't move as much. The shorter the piston stroke, the slower the bolt travels. I can't remember if screwing in in makes the pistom move less.
It should be easy to check. With the action out of the stock and the bolt locked open, check the piston to see how far it moves from the gas cylinder. Then adjust the screw so that it doesn't moves as much. If I remember, the movement of the piston should be easy to measure.
Less movement = slower bolt speed
More movement = faster bolt speed
I'm sorry i don't have that rifle anymore or I could pull it out and be more descriptive.
