AR/M16 Aperture sights.

[dvdcrr]

We are getting ready to build/shoot an AR with carry handle sight. Dedicated aperture sighted outfit. I am excited about this. Please share any recommended sight-in procedures or instructions. What challenges or shooting activities do you do to have fun with your open sighted AR's/ other rifles?

[Charlie98]

I only run irons on my AR's... there is nothing esoteric about using them.

If you want something a little less bulky than a carry handle, check out the Daniel Defense A1.5 rear aperture sight.

Generically speaking, zeroing at 25M gives you an effective range of about 300M without sight adjustment, depending on the ammo you are using.

[pblanc]

The sight in procedure will vary significantly depending on whether you buy A1 or A2 sights.

[emcon5]

Assuming you are talking about standard military type sights, I would use the same recipe Highpower shooters have used for years, a 6 MOA round aiming circle with a 6:00 hold. I posted good printable versions of the 100 yard reduced targets here:

https://thefiringline.com/forums/sho...9&postcount=25

[dvdcrr]

NICE!

[dahermit]

Originally Posted by dvdcrr

We are getting ready to build/shoot an AR with carry handle sight. Dedicated aperture sighted outfit. I am excited about this. Please share any recommended sight-in procedures or instructions. What challenges or shooting activities do you do to have fun with your open sighted AR's/ other rifles?

I assume you are referring to the standard method the Army and Marines used when sighting in their M16's that started at 25 yards. I cannot help you with that inasmuch as they trained me with an M1 Garand set up with a "Battle Sight (setting).

However, if that is what you are looking for, just mention it and I am sure some of the "younger" guys will be able to help you.

It that is what you are looking for, I will be interested in finding out the process also as I am presently building an AR with A2 sights.

[44 AMP]

Go find a copy of the army or marine FIELD MANUAL for the M16. It will have a section on sighting the rifle. If its not identical to what you have, it will be close enough to get you in the ballpark.

Make sure you get the Field Manual (FM) not the tech manual (TM) the FM is instruction on the rifle for the user. The TM is instruction on the rifle for the repair shop.

For example TM 9-1005-249-34 was the shop manual for the M16 in the 70s when I was in. It would tell you how to install the sights, but not how to USE them. That's in the FM!

[pblanc]

Here is a Paul Harrell video that discusses methods for zeroing 20" barreled M16 rifles with A1 and A2 sights which may or may not be helpful:

http://www.youtube.com/watch?v=xHtEoRUakKk&t=1305s

The procedure Harrell uses for zeroing the M16A1 is not quite the same as what was taught by the Army, however. He also discusses an alternate way of zeroing and using the A2 rear sight.

[dvdcrr]

OK I have a 20" flat top with a detach carry handle. I sighted so at 50m (or close to it) it is zeroed on the 6/3 setting with 55 gr. ammo.
Then took it over to 200 m. on the same 6/3 setting and got 3 consecutive hits.

50m zero on the 6/3 setting sound right?

[pblanc]

Originally Posted by dvdcrr

OK I have a 20" flat top with a detach carry handle. I sighted so at 50m (or close to it) it is zeroed on the 6/3 setting with 55 gr. ammo.
Then took it over to 200 m. on the same 6/3 setting and got 3 consecutive hits.

50m zero on the 6/3 setting sound right?

Well, it's right if you say it is. There are lots of different ways to zero an AR. It is your rifle so you can do it the way you want.

The 50/200 yard/meter zero is very popular, providing a pretty flat trajectory out to a little beyond 200 yards or meters, with a rise or fall above or below point blank point of aim from about 10 yards to 225 yards of 2" or less. But that flat trajectory is a function of the ballistics of the 5.56x45 cartridge and has nothing to so with what setting on your rear sight elevation drum you happened to use when zeroing your rifle.

In other words, you could have zeroed your rifle at 50 meters using any setting on the rear elevation drum, and if you did not change that setting, you would have been on or very close at 200 meters.

The problem with your method, if there is one, is it isn't really utilizing the ballistic drop compensation built into the rear elevation drum of the A2 rear sight. That sight is basically designed to allow the rear sight to be elevated to predetermined settings to compensate for the bullet drop at ranges out to 600 meters. The markings on the drum correspond to target range in meters. The 6/3 setting refers to 300 meters with the peep set to its lowest elevation, and 600 meters if you rotate the drum one full turn higher. The "4" and "5" settings refer to 400 and 500 meters respectively.

The Army uses this sight to allow the rifle or carbine to be zeroed at 25 meters to provide a 25/300 "battle sight zero". So if you zero at 6/3 (with the elevation drum in the low "3" position) at 25 meters, and then shoot at 300 meters with the same setting, you should hit within a couple of inches of your point blank aim. You can now use the rear elevation drum to dial the rear sight peep up to compensate for bullet drop at longer ranges, using the "4" for 400 meters, the "5" for 500 meters, and the "6/3" setting for 600 meters.

The advantage of the 25/300 meter zero is it allows one setting to be used to score combat effective hits on a target out to around 350 meters. The disadvantage is the bullet will hit more than 8" above your point blank POA at maximum ordinate, the point at which the projectile trajectory has risen to its highest point above the sight axis, in this case around 185 meters.

It would be nice if the A2 rear sight on the detachable carry handle had a "2" setting to allow you to use it to sight in at 50 meters for a 50/200 battle sight zero, but it does not. Some people modify the A2 rear sight elevation drum to allow it to be rotated to a height below the 6/3 setting for just this purpose.

This webpage has much more information on zeroing the A2 sight on fixed and detachable carry handles than you will ever want to know. It also discussed the USMC method of zeroing the M16/M4 which is completely different from what the Army uses:

http://savannaharsenal.com/2017/04/0...2-type-sights/

[agtman]

The advantage of the 25/300 meter zero is it allows one setting to be used to score combat effective hits on a target out to around 350 meters. The disadvantage is the bullet will hit more than 8" above your point blank POA at maximum ordinate, the point at which the projectile trajectory has risen to its highest point above the sight axis, in this case around 185 meters.

Yeah, for a long time I was a big fan of the 50/200(or 250) yard zero for the iron sights on my ARs. I still have several 16" ARs zeroed for that range.

But any more, after shooting my 'Retro' A1 all summer (with 20" pencil barrel and triangle handguards - a 1965-era model), I've been experimenting with the old Marine Corp 36/300yd zero. With 55gn ammo, this zero yields a very flat trajectory for engaging targets anywhere from up-close/point-blank range on out to 300+yds.

[pblanc]

Yes, I like a 34-36 yard near zero (depending on whether you are shooting 55 grain M193 or 62 grain M855) a lot better than the 25 meter near zero used by the Army. I have one AR's back-up sights zeroed at 35 yards (a compromise for both cartridges) which provides a POI within 5 inches of point blank aim out to nearly 350 yards.

That is a great zero if you anticipate shooting out to 300 yards or a little beyond. My eyes are not really good enough to do that with iron sights. If I am shooting at 300 yards or beyond, I need a scope with decent magnification.

I prefer the 50 yard near zero for red dot sights or low, variable power scopes which will result in a hit within 2" of point blank aim out to 250 yards with either cartridge. Two hundred yards, or a little more, is about as far out as I expect to shoot with either iron sights or a RDS, or a scope with 4X magnification or less.

I also like the Knight's Armament micro rear flip-up sight, which is used by the USMC. This does have a 200 meter setting which allows for a 50 yard/meter near zero. That sight also provides for ballistic drop compensation out to 600 meters, if your eyes are good enough.

[ThomasT]

Thanks for the link to the proper way to set your sights on an AR. I thought I had it figured out but now I am confused and I have read it twice now. I didn't realize the small and large peeps were made to give different POI when the small aperture was used.

I doubt I would ever shoot past 300 yards with my AR. I will most likely zero with the small opening a little high at 100 yards and see where it falls at 200 and 300 yards. The same thing I do with my deer rifle. Sight in about 2" high at 100 yards and I should be zeroed at 225 and 8-10" low at 300 yards.

I need to get a front sight tool. Any suggestions? I also wish there was a rear sight blade that was the same height from the small to large opening to fit the RRA carry handle I use.

[pblanc]

Assuming you have an A2 front sight post, you need a tool with 4 prongs to fit into the 4 notches of the flange. If you have an A1 front sight post with 5 notches on the flange, you need one with 5 prongs, obviously.

There are tools for both and some tools have 4 prongs on one end and 5 prongs on the other end. I have found that with the cheapest tools a prong will sometimes break off. But good tools are not very expensive. There are a ton of them for sale on Amazon for $10 or less, including one from Troy Industries for $9 which should be pretty good.

If you are shooting 55 grain M193 FMJ, with a 200 yard zero you will hit about 1" high at 100 yards. For a 300 yard zero you want to hit between 3 1/4 and 3 1/2" high at 100 yards.

[ThomasT]

Hi pblanc. I went and got my AR and used a laser bore sighter and it showed I was several inches high at 100 yards with both apertures. Especially with the small aperture and the rear cranked all the way down.

My rear sight was on it lowest setting and the rear was bottomed out. Its not going any lower. So I raised the front sight a total of two rotations using a punch to hold down the plunger and needle nose pliers to turn the sight.

Now I am what looks to be around one inch high with the large sight and ~2" or just a little more with the small sight. That should be close enough for me. I am not real worried about 300 yard shots. Two hundred would be closer to the max I would shoot.

I checked my Speer ballistic chart and 2" high at 100 yards should be dead on at 200 and 10" low at 300. Close enough for me. My front sight is just a little higher than the sight shelf by about 1/16". I could probably use the taller Bushmaster sight mentioned in the article but its not a half to have thing. And I did find the sight tools on Midway USA for around $10. I will order one next time I order from Midway. I have list going now.

Thanks for your help. I haven't shot this rifle much since I bought it right after the Sandy Hook fiasco and just before the prices went nuts. Believe or not I have only fired 80 rounds so far.

[Dfariswheel]

An interesting sighting method for the AR-15 rifle and carbine are the Santose Improved Battle Sight Zero and the Santose Revised Battle Sight Zero.

One method gives a battle sight that will allow hits on target within a 5 inch circle out to 230 meters without changing the sight setting.

The Revised system is for use on American ranges laid out in yards.
This method allows shooting at 50 and 100 to 150 YARDS and hitting.

Both methods still allow using the 300 to 600 or 800 METER sight adjustments.

https://www.ar15.com/forums/ar-15/-/18-328143/?

I set up to use the Revised method and my Colt M4 is dead on at 50 and 100 yards.

[pblanc]

The thread on AR15 dot com, while good, is hard to follow with all the illustrations and photos that are defunct. Both the "Santos improved" battle sight zero and the "revised improved" battle sight zero are discussed in the link I previously cited, which is here:

https://savannaharsenal.com/2017/04/...2-type-sights/

It is necessary to scroll a little more than halfway down the page to get to the Santos IBZ and the RIBZ follows.

Briefly, with the Santos method the rear sight elevation drum is reset so that the rear sight peep aperture can be lowered two clicks below the "8/3" setting for fixed carry handle A2 sights, and usually four clicks below the "6/3" setting for removable carry handle A2 sights. The lowest settings on the drum are then referred to as "8/3-2" or "6/3-4" respectively. You then zero at 50 yards (not meters) using the small aperture with the drum at the new lowest setting (e.g, 6/3-4), adjusting the height of the front sight post to zero elevation. This new lowest setting of the elevation drum then provides for a 50 yard/200 meter zero. You will still hit a bit over POA at 100-150 yards. The "6/3", "4", "5", and "6/3" settings are then used for 300, 400, 500, and 600 meter range compensation.

The RIBZ method modifies the rear drum so that it will depress the rear peep further, a full 6 clicks below the "6/3" setting, which would be referred to as "6/3-6". This new low setting is used for ranges of 100-150 yards. With the rear sight elevation drum set 2 clicks above that new lowest setting (6/3-4), you again zero at 50 yards using the small peep aperture. The settings on your modified rear elevation drum will now be set to approximately compensate for ballistic drop at the following ranges (for a 20" barrel shooting 55 grain M193 or 62 grain M855):

Rifle with 20″ Barrel and Removable Carry Handle:

25 meters: “Z” setting
50 yards/200 meters “battle zero”: “6/3 -4”
50 yards: “6/3 -4”
100 yards: “6/3 -6”
150 yards: “6/3 -6”
200 meters: “6/3 -4”
300 meters: “6/3” (or “8/3″ with fixed carry handle, 20” barrel rifles)
400 meters: “4”
500 meters: “5”
600 meters: “6/3”

I don't use removable carry handles with A2 sights, but if I did, I would probably modify them per the RIBZ method.

[ThomasT]

I watched the Paul Harrell video linked above and I am close to what he was saying for an A2 sight set up. But I need to get to the range and do the shooting. I didn't realize how versatile the sights on the AR were.