Loosen the lock ring on the die then screw it clockwise about 1/16th of a turn.
As you found out, even 1/16 of a turn will result in a significant change in headspace. And now consider the normal die manufacturers directions to turn the die in 1/4 to 1/2 turn past the point where the die contacts shell holder. To give you a better idea of the "sensitivity" of die adjustment, use the guide developed by UncleNick.
Good for you to measure and set your headspace properly!!!!