Halfway through a JCG match this past weekend, my shots started stringing vertically down towards the six ring. I realized that the screw in the elevation knob was loose and the aperature had slipped down. I took a dime and tightened the screw. Ensuring the aperature was bottomed out, I then raised it 13 clicks and continued the slowfire string. All subsequent shots were in the black. Other than blue loctite, is there a remedy to preclude any futher problems?