Zeroing A2 Irons for 50 Yards?

[wintermute]

Sorry that this is such a newbie question, and I'm wracking my brain trying to figure out how to do this... Right now my new carbine (Colt 6400) is equipped with an A3 carry handle. I don't plan to switch this out for a while for something like a Troy BIUS and an Aimpoint due to funds. So, since I don't really expect to do much shooting with this at ranges over 200 yards it seems like it makes sense to zero the sights at 50 yards so I don't have to make too many adjustments for range. How would I go about doing this?

[markm]

Get a solid table and piece of artificial supports and go to it. Get a good target that your can see well when you're focusing on the front sight, but still forces you to aim precisely.

adjust your windage with the rear sight and your elevation with the front sight post. I like to zero my carbeans at 50, but I zero them so the POI is 1" low. I've found that if I do this my 100 yard precision shot is dead on. When I give my carbeans a true 50 yard zero my POI at 100 is a little too high.

[andy t]

50 yard is actually a very useable zero. I use it on all of my AR's.
Here is the target I found very helful for zeroing: Zeroing target (http://www.brownells.com/.aspx/pid=20847/Product/SIGHT_IN_TARGET)
If you are shooting at 25 yards, you want POI to be about 1.5" below POA.

[wintermute]

I know how to sight in in general - this is just the first gun I've owned with military sights. I guess since the ranges are so short I can ignore the elevation dial on the rear sight? What should I have the elevation dial set to? Thank you.

[andy t]

I usually just bottom out the elevation dial on the rear sight.
Caveat: Zero with the aperture you plan on using, since they are designed to be used for different distances - on the detachable carry handle. Since I view my rear irons as backup, I always use the large aperture for zeroing.

[jmart]

Do a search on IBZ or "Improved Battlesight Zero". This will walk through the zeroing process for adjustable elevation rear sights. If not found here you can find it on ARFcom. It actually is one of the more useful topics/threads hosted over there.

[markm]

What should I have the elevation dial set to? Thank you.

The elevation dial should be set to where the 6/3 or 8/3 flat on the elevation wheel is facing the opposite side of the windage dial. You should be able to feel that your elevation is set there without looking by using your right hand thumb.

You won't need to ever mess with the elevation wheel inside of 300 yards really. I dial mine up when I'm shooting 400 yards or more, but that's not too often.

Your zero should be with the small app and the wheel positioned where I mentioned above.

[glockshooter]

On a2 sights the rear sight will move POI 1 cm for every
three clicks and the front sight will move POI 1 cm at 25 meters. So if you are going to do a 50 yard you just need to keep in mind the shift will be approximate twice
the 25 meter values I listed. Hope this helps.

Matt

[wintermute]

Thanks all! One stupid question for markm: why should I zero with the narrow aperture? Won't this provide a different POA than the large aperture (which I'll be using 99% of the time)?

[openbolt]

Thanks all! One stupid question for markm: why should I zero with the narrow aperture? Won't this provide a different POA than the large aperture (which I'll be using 99% of the time)?

Not markm but I believe the aperture is "same plain" meaning unlike the old A1 rear aperture where when you flipped it you got some instant elevation, with the A2 style rear your elevation is going to only come from the elevation wheel. I too use the small peep when sighting in as it's more precise.

openbolt

[WGG]

You can use this target for zero at 25\300 meters.

http://www.macksworld.net/external/targets/Targets/Sighting/PDF/Click-n-Shoot%20%23M16W.pdf

[ForTehNguyen]

Thanks all! One stupid question for markm: why should I zero with the narrow aperture? Won't this provide a different POA than the large aperture (which I'll be using 99% of the time)?

its easier to center and more consistent, everything you need when you zero

[RogerinTPA]

You can use this target for zero at 25\300 meters.

http://www.macksworld.net/external/targets/Targets/Sighting/PDF/Click-n-Shoot%20%23M16W.pdf

A very recent article by a Army Infantry Major (Take back the Infantry half Kilometer) stated that a 25/300 yard zero will result in misses at 100 and 200 yards due to the trajectory being too high (8-15 inches) at those intermediate ranges. All of the former SFOD types that are now trainers recommend a 100 yard zero, but the most practical is the 50/200 yard zero, at least for me for the past few years. It gives you a maximum height in trajectory within 2 1/2 inches from barrel to POA at 50, and again at 225 yards. It is also advocated in the article.

[RogerinTPA]

Thanks all! One stupid question for markm: why should I zero with the narrow aperture? Won't this provide a different POA than the large aperture (which I'll be using 99% of the time)?


The Army did a study that determined that the size of the aperture being used was based solely on individual preference. I like the smaller aperture since the larger one has too much "air" in it for me. In my mind, it's akin to the "aim small, miss small" axiom.

[markm]

Thanks all! One stupid question for markm: why should I zero with the narrow aperture? Won't this provide a different POA than the large aperture (which I'll be using 99% of the time)?

I don't know anyone who can hit anything with that stupid large app. I'm a pretty damned good rifle shooter... and when I shoot the large app... it's like shooting blind folded.

The large app is certainly not on the same plain.... I don't know where it is, but I can't bring myself to waste the ammo trying to figger it out.

[ABN]

Zero with the small app., I'm not gonna reference the marksmanship FM, but with a 25/300 zero it does recognize adjusting aiming points at 150-200, essentially its 150-waist, 200 belly.

With modern weapons there is no need for the large app., at one point it may have been good for nbc firing and moving targets. With modern optics its pretty much outmouded

[wintermute]

Thanks all - going to do the mods for Improved Battlesight Zero and then hit the range.