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 So what is the purpose of the large aperture rear sight on AR-15?
Lindy_Hoppin_Gun_Nut  [Member]
9/27/2006 6:14:54 AM EST
Does anybody know how to use it properly AS IS without any modification? That large aperture sight is not on the same plane with the one with the small hole. I can't even hit the paper at 100 yards using the large aperture sight because I ended up shooting waaaaaay low.

I found out that using the large hole sight, I shoot more than a foot low at 25 yards, so how does the ARMY train their soldiers in using the large aperture sight (or is it use AT ALL other than for clearing houses)? I've heard the Marines don't even use it.

I know I can modify / tweak the sight (using Chuck Santose's method for example), but just let me say that anything I touch turn into sh**t, so I'm hesitant to mess with it.

Thanks!
Lindy
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NoAim  [Team Member]
9/27/2006 7:05:24 AM EST
They are supposed to be on different planes


The rear sight has an elevation knob with range indicators from 300 to 800 meters and two apertures for range. One aperture is marked 0-2 for short range from 0-200 meters and the unmarked aperture for normal range from 300 to 800 meters. This unmarked aperture is used in conjunction with the elevation knob for 300-800 meter targets.


AR-15 Sight-in Guide
Lindy_Hoppin_Gun_Nut  [Member]
9/27/2006 7:09:47 AM EST
Thanks, NoAim! But still, even when the 300 m zero is established (using the small hole / unmarked sight), the large aperture sight will cause you to shoot very low, causing you to miss the target even at 100 meters
specter_actual  [Team Member]
9/27/2006 9:23:15 AM EST
the large sight is also used if firing with a promask
21BoomCBTENGR  [Team Member]
9/27/2006 9:40:58 AM EST

Originally Posted By Lindy_Hoppin_Gun_Nut:
Thanks, NoAim! But still, even when the 300 m zero is established (using the small hole / unmarked sight), the large aperture sight will cause you to shoot very low, causing you to miss the target even at 100 meters


it's used for firing at Night, i think theres some sort of mental thing that causes people to shoot high at night which is why the sight causes hits to be lower, alsoits easier to sight with at night.
p-dog  [Member]
9/27/2006 4:17:18 PM EST
If you look closely, the large aperature is marked "0-2".

This means that if the small aperature is zeroed for 300m, the large aperature should be on at 200m. This is about the maximum point-blank range, i.e. the zero where any range closer will be off by no more than about 2" in elevation.

The large peep works like a "ghost ring" & allows quicker sight alignment. The trade off is some loss of accuracy.

I have no problem with the zero of either of my rifles when switching back and forth between the aperatures. I can only guess that you have an out-of-spec sight, or you're not holding a correct sight picture.
DocGP  [Member]
9/27/2006 5:34:58 PM EST

Originally Posted By p-dog:
If you look closely, the large aperature is marked "0-2".

This means that if the small aperature is zeroed for 300m, the large aperature should be on at 200m. This is about the maximum point-blank range, i.e. the zero where any range closer will be off by no more than about 2" in elevation.

The large peep works like a "ghost ring" & allows quicker sight alignment. The trade off is some loss of accuracy.

I have no problem with the zero of either of my rifles when switching back and forth between the aperatures. I can only guess that you have an out-of-spec sight, or you're not holding a correct sight picture.


+1, all mine hit just fine with the large aperture. I mostly shoot 50-100yds, and have had no problems (other than that I shoot like KAKA!!!)

Doc
Combat_Jack  [Member]
9/27/2006 5:42:32 PM EST

Originally Posted By 21BoomCBTENGR:

Originally Posted By Lindy_Hoppin_Gun_Nut:
Thanks, NoAim! But still, even when the 300 m zero is established (using the small hole / unmarked sight), the large aperture sight will cause you to shoot very low, causing you to miss the target even at 100 meters


it's used for firing at Night, i think theres some sort of mental thing that causes people to shoot high at night which is why the sight causes hits to be lower, alsoits easier to sight with at night.


Actually the rule of thumb is the opposite. Lights up, sights up.
21BoomCBTENGR  [Team Member]
9/27/2006 6:29:31 PM EST

Originally Posted By Combat_Jack:

Originally Posted By 21BoomCBTENGR:

Originally Posted By Lindy_Hoppin_Gun_Nut:
Thanks, NoAim! But still, even when the 300 m zero is established (using the small hole / unmarked sight), the large aperture sight will cause you to shoot very low, causing you to miss the target even at 100 meters


it's used for firing at Night, i think theres some sort of mental thing that causes people to shoot high at night which is why the sight causes hits to be lower, alsoits easier to sight with at night.


Actually the rule of thumb is the opposite. Lights up, sights up.


huh, ok. i always tried to shoot at the muzzle flashes/where the tracers were coming from.
Sgt_Gold  [Member]
10/1/2006 6:48:01 AM EST
This is true for target shooting, but has no application in real life. The large ghost ring on the M16 rear sight is for night firing. Once your eyes have adjusted to the ambient light, the large ring gives you enough light to allow you to use the sights.


Originally Posted By Combat_Jack:
Actually the rule of thumb is the opposite. Lights up, sights up.
TheRedHorseman  [Team Member]
10/1/2006 6:51:53 AM EST

Originally Posted By Lindy_Hoppin_Gun_Nut:
Thanks, NoAim! But still, even when the 300 m zero is established (using the small hole / unmarked sight), the large aperture sight will cause you to shoot very low, causing you to miss the target even at 100 meters


funny, I shot sharpshooter(32 out of 40) on an automated range using an M4 that I left on the large aperture for shits and grins since we had a pile of ammo to burn. I dropped all the 300 meter targets just fine.
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