I have a 725 Sporter with the single Allen key in the Butt Pad to adjust the comb. I was wondering if this style of adjustable comb can be removed and spacers put in. I have found it occasionally moves. I have tightened the Allen key to where I think it should be. I do not want to over tighten. I would just fit rubber/plastic washers to keep the height . The owners manual does not show it being "removeable".