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Old February 12, 2013, 11:49 AM   #1
Robert37803
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Help with elevation on AR iron sights

I posted this in the semi auto, but thought it might be better here.
I am planning on shooting NRA highpower matches this spring but don't have a place to check my hand loads for 300 & 600 yards. I am using 77g SMK for 300 & 80g SMK for 600 yards. My White Oak upper has a 1/4 min. A2 style rear sight. Could someone give me a starting point for these loads and distances. Thanks in advance for the information.
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Old February 12, 2013, 12:49 PM   #2
emcon5
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http://www.jbmballistics.com

Measure your sight height, put in the altitude of the range and your muzzle velocity and go from there.

If you put in good data you should be on paper with no problem.
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Old February 12, 2013, 01:31 PM   #3
kraigwy
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I use the same loads, ()77 SMKs at 2&300 yards, 80 SMKs at 600 & 1000) in my White Oak Service Rifle.

Mine has 1/2 MOA Clicks. I zero at 200, come up 6-8 clicks to 300, and I use 26-28 at 600. (Depending on weather conditions).

For 1000 yards I use my 600 zero and turn my front sight 4 full revolutions down.

For 100 yard practice on the NRA 100 yard reduced targets I use my 200 yard zero and turn the front sight UP one full revolution.

Again I have 1/2 min clicks, if your's is 1/4 you'll double those numbers.
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Old February 12, 2013, 06:29 PM   #4
PawPaw
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Quote:
For 1000 yards I use my 600 zero and turn my front sight 4 full revolutions down.
Seriously, Kraig, you're shooting a .223 to 1000 yards? I didn't think that those 80 grain pills would travel that far. What twist are you using?

(I don't doubt that you're doing it, I'm just amazed.)
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Old February 12, 2013, 08:19 PM   #5
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1:7

The AR 223 is pretty common in 1000 yard service rifle shooting.
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Old February 12, 2013, 08:47 PM   #6
Robert37803
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Thanks Kraigwy. This information will help. If I may also ask how far down do you zero your rear sight? All the way down, or do you leave a few clicks for adjustments for shorter distances?
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Old February 12, 2013, 09:56 PM   #7
kraigwy
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My rifle is sighted in at 200 when the rear sight is bottomed out.

That way its easier to quickly return to zero.

I do a lot of practice at 100 on the NRA reduced targets. Using my 200 yard zero (bottomed out) I'm on at 100 if I turn the front sight UP one full revolution.

Then, when I move to 1000 from 600, I leave the rear sight alone and turn the front sight down 4 full revolutions.

Depending on the enviormental conditions (light, temp, etc) I use the rear sight to fine tune it.
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Old February 13, 2013, 10:00 AM   #8
Robert37803
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That works for me. Thanks for the information.
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Old February 14, 2013, 07:05 PM   #9
30Cal
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Good for you! Show up and shoot! Don't sweat zeros, lack of gear or practice. You really can't learn hardly anything until you're shooting for record.

Kraig's zero ought to get you on paper. Good nuff.
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Old February 15, 2013, 07:48 AM   #10
Bart B.
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PawPaw, folks have been shooting the 5.56 NATO round in 1000 yard matches since it was first allowed in competition back in 1971. While it's initial performance that far down range was dismal at best, later on with heavier bullets and faster twists, it did pretty good.

But it's never been the equal of the 7.62 NATO round at 1000. Which is why the US Army Rifle Team quit using it in long range matches a year or two ago and got the rules changed to allow the AR10 in 7.62 NATO be designated a "Service Rifle" for competition; they no longer had any good M14NM's to use. People shooting 7.62 NATO ammo in Garands and M1A's were shooting better scores that those using the 22 caliber round.

Never the less, it's fun to shoot those tiny bullets at things way far away. And some folks get really good at it.
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Old February 19, 2013, 09:22 PM   #11
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I use a little bit different sight setup, but the same 77/80 gr SMK's. I have a custom 1/4 min on my service rifle built by the AMU and my 200 yd zero is set up at one full rotation of the elevation dial + 5 clicks (or 7.25 min from the bottom). I bottom the sight and make witness marks on the dial, make a full rotation up and another 5 clicks to my 200 yd zero. I add +2 clicks (1/2 min) for sitting at 200. For 300 I add another 8 clicks (2 min) from my sitting . At 600 I dial in 3 rotations + 5 clicks or an additional 10.25 minutes from my 300 yd zero. This sight has rediculous consistency, repeatabiliy and elevation range.

Basically I dial in my zero's by starting at 1+5, then move to 1+7, 1+15 and then 3+8. Might sound complicated at first, but it is actually super simple, easy and fast to check prior to the stage. I always try to recheck zero's the day before or day of match as they fluctuate slightly depending on conditions. If I can't check my zero I trust my settings and experiences as documented by my day book and make corrections.
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Old February 22, 2013, 05:33 PM   #12
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Just to note, your rear sight should be at the same setting regardless of where you end up zero'ing it. In the front you can press a detent pin through a hole, and spin the ring back to the 3/6 mark.
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