Let me preface this by saying one of the muzzleloading guys at the range gave me his old 45x spotting scope, because, he said, he tried to sell it and no-one bought it!  Score!

Anyway, I followed the directions for the IBSZ on the Maryland AR-15 shooters site and sighted-in at 50 yards.

The best group of 3 I was able to shoot was about 4 inches so I guess it isn't as easy as it looks...
EDIT: I just looked at my target again and , go figure, my first group was about an inch and a half, and got worse from there (even though I got closer to the bullseye as I adjusted the front site...I think its cause the daylight was fading fast)

So my biggest question is when you are out at 50yards and beyond, when your target (I used the bushmaster sighting-in target) is the same size or smaller than your front sight .. how should I set it up for point of aim:  should the front site COVER the area I want to impact, should the very top edge be where I want it to impact, or should I want to impact just slightly ABOVE the front site?  I really have no idea.

Also, I set it up 4 clicks down from 6/3 on my A3 sight ... I am just supposed to leave it there and not move it back to 6/3 unless I am shooting at 300 m ?

Thanks all.

bump to top?

maybe everyone is off at gunstock

I cant really say I know the RIGHT way to do it... but I have always planned on sighting in a gun with Iron Sights to put the bullets right on the top of my sight post.... so I can still see what Im shooting at, and can line it up with the post.

Other wise when you cover it, you can tell if you drift slightly off the left or right... however if the post is right below the target, you just line it up with teh center...


I hope this makes sense.  Hell, All my rifles have scopes...

Quoted: Let me preface this by saying one of the muzzleloading guys at the range gave me his old 45x spotting scope, because, he said, he tried to sell it and no-one bought it!  Score! Anyway, I followed the directions for the IBSZ on the Maryland AR-15 shooters site and sighted-in at 50 yards. The best group of 3 I was able to shoot was about 4 inches so I guess it isn't as easy as it looks... EDIT: I just looked at my target again and , go figure, my first group was about an inch and a half, and got worse from there (even though I got closer to the bullseye as I adjusted the front site...I think its cause the daylight was fading fast) So my biggest question is when you are out at 50yards and beyond, when your target (I used the bushmaster sighting-in target) is the same size or smaller than your front sight .. how should I set it up for point of aim:  should the front site COVER the area I want to impact, should the very top edge be where I want it to impact, or should I want to impact just slightly ABOVE the front site?  I really have no idea. Also, I set it up 4 clicks down from 6/3 on my A3 sight ... I am just supposed to leave it there and not move it back to 6/3 unless I am shooting at 300 m ? Thanks all.

First of all, I'm trying to help, so please accept my criticisms as constructive, OK?

- Sighting in at 50 yards was good.
- At 50 yards, making sight adjustments based on a 4" 3-shot "group" is very iffy.  Groups should be no larger than an inch or so at this range - all 3 rounds touching would not be unusual.  Try again when you have better light.
- The very top of the front sight post should be where the bullet impacts.  If aiming at a circle, top of front sight post in center of circle.
- If you sighted in with the SMALL aperture, then yes - leave the elevation knob where it is (4 clicks down from 6/3) unless you shoot at 300 with the SMALL aperture.  If you want to use the LARGE aperture (for better target ID in low light and fastr target acquisition at closer ranges) then set the elevation knob back to 6/3.  The reason you have to do this is the small aperture hits to a higher Point of Impact tha the large aperture.  So, for a given Zero, when switching from small to large aperture, you have to raise your rear sight.

Clear as mud, right?

Anyway, you are on the right track - keep us posted.

I have a new AR as well. When sighting-in, should it be conducted off-hand or using a rest?

Quoted: I have a new AR as well. When sighting-in, should it be conducted off-hand or using a rest?

When sighting in a new rifle of any sort --- irons, scopes, ACOGs, etc. I always start on a rest. This way you know exactly what your weapon and sights are doing without complicating it with your own shooting inconsistancy.

After this, if I know I will most likely be shooting off hand (ie--12ga slug for deer) I will practice off hand and tweak as needed.

Quoted: I cant really say I know the RIGHT way to do it... but I have always planned on sighting in a gun with Iron Sights to put the bullets right on the top of my sight post.... so I can still see what Im shooting at, and can line it up with the post. Other wise when you cover it, you can tell if you drift slightly off the left or right... however if the post is right below the target, you just line it up with teh center... I hope this makes sense.  Hell, All my rifles have scopes...

I also set POI directly on top of my sight pin. Helps me a lot on longer shots.

You are confusing two things.  Shooting to adjust point of impact to point of aim and shooting for groups size.

Two completely different things.  If your 4" group is centered around your point of aim, your sighting in was done correctly.

Now you have to figure out if the 4" group is due to ammo, rifle, or shooter.  I'd bet it's the shooter first, then ammo, then rifle.

Quoted: First of all, I'm trying to help, so please accept my criticisms as constructive, OK? of course, thanks for the help! - Sighting in at 50 yards was good. - At 50 yards, making sight adjustments based on a 4" 3-shot "group" is very iffy.  Groups should be no larger than an inch or so at this range - all 3 rounds touching would not be unusual.  Try again when you have better light. I think the near absence of daylight was the major factor..I mean, my first group was about an inch, then they got bigger, and I finished up around 6:45 here which is pretty dark this time of year.  I also re-looked at my target again today and that first group was about 1 inch, the others were about 2, 2 and a half, and there was one  group of two about an inch apart with a flyer 3 inches or so away. next time I will do 5 shot groups?  the bushmaster instructions said 3 which is the only reason i did three. - The very top of the front sight post should be where the bullet impacts.  If aiming at a circle, top of front sight post in center of circle. this is a HUGE help, i had no idea which way to do it yesterday - If you sighted in with the SMALL aperture, then yes - leave the elevation knob where it is (4 clicks down from 6/3) unless you shoot at 300 with the SMALL aperture.  If you want to use the LARGE aperture (for better target ID in low light and fastr target acquisition at closer ranges) then set the elevation knob back to 6/3.  The reason you have to do this is the small aperture hits to a higher Point of Impact tha the large aperture.  So, for a given Zero, when switching from small to large aperture, you have to raise your rear sight.

Quoted: You are confusing two things.  Shooting to adjust point of impact to point of aim and shooting for groups size. Two completely different things.  If your 4" group is centered around your point of aim, your sighting in was done correctly. Now you have to figure out if the 4" group is due to ammo, rifle, or shooter.  I'd bet it's the shooter first, then ammo, then rifle.

No, I understand the difference, I was just commenting that my consitency got worse even as the day went on , although my adjustments for point of impact:point of aim got closer.

The 4" group was really a group of two about an inch apart with another flyer several inches away.  I will use 5 shots next time, that sounds like a better plan.