It's not really that hard, I was hitting a barn after the first 500 rounds!

With conventional sights on a pistol, I have a problem lining up the square
notch rear with the square front post. My eyes just don't want to get things the way they should be. Now with a V rear sight and round post front, I do a LOT better.

http://navyadvancement.tpub.com/12018/css/12018_387.htm

http://www.firearmsprimer.com/marks/marks_3.htm

Here is all you need to know about aiming a firearm (with iron sights)
http://www.firearmsprimer.com/marks/marks_3.htm

Now of course, at longer ranges you WILL need to raise your front sight above the height of the rear sight (as he explains toward the end of the video)

AND if all else fails, ask JJ to explain it for you, I am sure that he can do a lot better job than I can. <img src="/ubbthreads/images/graemlins/thumbup.gif" alt="" />