Hello and welcome to the forum.It may not be the position of the sights.My CS9 was low to point of aim and I accidentally found the "cure" for it when I took off the Novak lo mount sights and replaced them with the Trijicon night sights.This brought it right to point of aim.When others were having the same problem with thier CS9's I told them about my observations and when they did the same thing they had the same result.I do not know if this might be the case with the CS40 but it may be worth a try.If it is still a little off you have nice night sights to adjust.......MIke