I just bought a $20 Laser Sight that easily fits on my HK Full Size USP's rails. I've had trouble zeroing it. I adjusted it the best I could, but are finding that there seems to be no way to zero it perfectly for all ranges. If you get close enough to the target, the laser points down below the barrel. Opposite happens as you get far enough away from a target. I'm forced to practice and remember that my rounds will go either above or below the laser point when aiming with the laser pointer. I'm thinking that maybe the laser pointer sight is just for close quarters. My USP is being used as Home Defense. Can anyone help me out with this? Does anyone have experience with this? Maybe I just have a cheapo laser sight, and have to deal with a much more expensive one?