This is the first time trying to do this. I went out to zero the sights on my rifle. "16 flat top with ARMS #40 sight. I tried the 25 meter zeroing method and was getting some okay groups at that distance. I moved it out to 100 yds and couldn't hit the paper. I was using a 100 yd. sighting target with the 4 diamonds in the corners and one in the middle, so it's pretty big. Maybe it's a misunderstanding on my part as far as where the front sight post should be in relation to where I am intending to hit at further distances. At 100 yds. I had the top of the post in the middle of the center diamond. Where should the post be? Next time I go out I will start again at 25 meters and try to get tighter groups then work my way out but any suggestions would be helpful. Ammo used was remington umc 55gr.
               Thanks    

For zeroing method read here: [url]http://groups.msn.com/TheMarylandAR15ShootersSite/zeroingmethods.msnw[/url]

I like the 50 yard "Santose" method, personally.

The important thing to remember w/ iron sites is to be consistent with your cheek to stock placement, which is why so many espouse the "nose to the charging handle" technique. Also as ARMS#40 has no elevation adjustment you'll have to use your front sight inorder to make elevation changes. Most of my 16" M4s need the front sight lowered to abtain a proper zero using the ARMS BUIS. YMMV

Tip: While maintaining this front sight-rear sight alignment, move the rifle until the front sight covers the target or sits just under it. Most target shooters like to see the bullseye, just above the front sight post. When the bullseye appears to sit atop the front sight in this manner, you're employing what's known as a "6-o'clock hold."

Using Military Peep sights: To use this kind of sight, you simply look through the rear aperture or "peep," and place the front sight on or immediately under the target. You needn't concentrate on the rear sight at all; in fact it should appear as an indistinct blur. Your eye will automatically center the front sight at the strongest point of light, which falls at the exact center of the rear aperture.

Mike

added: new thread this am shows AR sight picture: [url]http://www.ar15.com/forums/topic.html?b=3&f=118&t=172199&w=activePop[/url]

If you zero at 25m, you are likely to be quite hight at 100.  I can't remember how high, but it might be off the paper.

Remember if you zero at 25 yards (or meters) your round will be 6" (+) high at 100 yards (and still rising).

Those of us that shoot alot much prefer the 50y Santose IBSZ.  Zero at 50 yards (piont of aim=point of impact).

Now your round will travel within 2" of the point of aim from 8m to 220M (assuming a 14.5" barrel and M193).  So you can hit soda cans all day long with a center of mass aiming point out past 200 yards.

Besides checking out the zeroing method mentioned above, also check out the Sights/Optics FAQ on that same website (there are pictures on how the sights should be used).[url]http://groups.msn.com/TheMarylandAR15shootersSite/sightsopticsfaq.msnw[/url]