Totoe,
A good way to check to see if your crosshair is aligned correctly is to put up a turkey pattern target @ 10 yds., back up and take a nice steady aim at the center of the neck on the target and let a round fly. If you are sighted correctly, there should be a nice, neat hole about the size of a golf ball right where you aimed if you are using a tight turkey choke. When you get it right @ 10 yds., back up to 20, 30, and 40 yds. and keep aiming at the center of the neck. Your patterns should be pretty evenly spaced on the target using this method. Hope this helps.