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sighting in 5.56 ???

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March 30, 2019, 07:01 PM
Harleysbluff
sighting in 5.56 ???
Gentleman -

How do you guys sight in your 5.56's? I know it depends on the type of shooting you do, but I've heard two different ways.

1) Dead on at 100 yards

2) Dead on at 50 yards

Thoughts ? Thanks.

MDS
March 30, 2019, 07:11 PM
RHINOWSO
I use these, the zero for 100yards at 25 yards - nats ass it, then kick it to 100yds to verify, because if you don't check it at the range, it's only a guess IMO. Plus it can / will vary depending on your optic height over bore, ammunition, etc, etc.

http://www.arma-dynamics.com/r...ot-zero-targets.html

I prefer to have a zero at 100, so the bullets are always at or below the zero, not above and below. And since most of my shooting is 100-125yds and in, I'm good to go.
March 30, 2019, 07:57 PM
gearhounds
Zero at 100. You’ll hit fine within 100, and easily keep in a silhouette out to 300.




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March 30, 2019, 07:59 PM
IndianaBoy
Depends on the optic and reticle.


50 is a recipe for failure if you ever shoot out to 400+.

I always confirm zero out to the farthest distance I will shoot.
March 30, 2019, 08:00 PM
IndianaBoy
Most of my ARs are zeroed at 200 at the main crosshairs.
March 30, 2019, 08:03 PM
Harleysbluff
I should add - I’ll never shoot more than 200 yards

Colt 6920 SOCOM w/ ACOG 4X

MDS
March 30, 2019, 09:49 PM
sigfreund
This is a question best answered with more input and then by examining actual trajectories calculated with something like the JBM solver.

The things that make a difference include the specifics of the gun and sight, the velocity of the bullet and its ballistic coefficient, and the type of target. Hunting prairie dogs requires much greater precision and accuracy than banging steel silhouettes.

Just as a few examples, though, I used JBM to calculate the ballistics of M193 55 grain FMJ ammunition at 3040 fps (16" barrel) under “standard” atmospheric conditions and sight height of 2.8 inches.

With the following zero distances, the bullet will be above or below the line of sight by the number of inches indicated:
25 yard zero: 50y +2.6"; 100y +6.8"; 200y +11.6"; 300y +10.0"; 400y 0
50 yard zero: 50y 0; 100y +1.7"; 200y +0.7"; 300y –5.3"; 400y –20.4"
100 yard zero: 50y –0.9"; 100y 0; 200y –2.1"; 300y –10.5"; 400y –27.3"

I recommend a 50 yard zero for police patrol rifles because out to 300 yards it requires the least point of aim adjustment. In fact, to 200+ yards with human-sized targets, good hits will be achieved by simply aiming at center of mass. Of course that will also be true of a 100 yard zero. And as mentioned, a 100 yard zero requires a positive holdover at all ranges except 100 yards. That can make things simpler for certain situations, particularly if one is making precise elevation adjustments with a scopesight elevation knob or calibrated reticle.

However, as a practical matter if absolute accuracy isn’t required, zeroing at 50 yards is simply easier for most people, especially when using nonmagnifying sights like the EOTech, Aimpoint, or countless others.

With a 4× ACOG, though, I personally would probably zero at 100 yards, especially if using better ammunition than military grade stuff.
All my precision rifles are zeroed at 100 yards for the type of shooting I do with them because it’s necessary to dial up for most distances and for ballistics calculation purposes.




6.4/93.6

“Wise men talk because they have something to say; fools, because they have to say something.”
— Plato
March 30, 2019, 10:22 PM
Harleysbluff
Great post - thank you

MDS
March 30, 2019, 10:51 PM
joatmonv
https://youtu.be/jttB1kUXfJE

This is what I went with. To each his/her own though.


I'd rather be hated for who I am than loved for who I'm not.
March 30, 2019, 11:38 PM
tigereye313
My AR with the Aimpoint Pro is 50/200.

When I get my 1-6 for my new AR it will be 100yds to take advantage of the reticle.




March 30, 2019, 11:46 PM
fritz
quote:
Originally posted by Harleysbluff:
I know it depends on the type of shooting you do, but I've heard two different ways.
1) Dead on at 100 yards
2) Dead on at 50 yards

It does depend on what type of shooting you plan to do. With an ACOG and target distances no greater than 200 yards, I suspect you're looking more at defensive purposes than precision target practice.

If this is a defensive firearm, then a zero at either 50 or 100 works. But I suggest a 50-ish yard zero is better. Your zero depends upon how you wish to use the reticle, and hold overs/unders for target distances not equal to your zero.
March 31, 2019, 07:00 PM
MikeinNC
I zero my Ars with iron sights at 1000 inches just like we did in the service. Balistically it’s the same as a 100 yard zero. With a scope I zero at 100 yards



"Violence, naked force, has settled more issues in history than has any other factor.” Robert A. Heinlein

“You may beat me, but you will never win.” sigmonkey-2020

“A single round of buckshot to the torso almost always results in an immediate change of behavior.” Chris Baker
March 31, 2019, 08:22 PM
gw3971

March 31, 2019, 11:35 PM
Alyron
My current department only allows iron sights and red dots (with magnifiers if you want) and zeros to 50 yards. My previous department we zeroed at 100. But we allowed certain scopes- I had an ACOG TA01. Most of the graduated scopes like that are set up to zero at a hundred.
April 01, 2019, 11:48 AM
ARMT Guy
quote:
Originally posted by Harleysbluff:
I should add - I’ll never shoot more than 200 yards

Colt 6920 SOCOM w/ ACOG 4X

MDS



Since you're using a 4x ACOG, zero it at 100 meters, like they're supposed to be.

What model of ACOG do you have?




"Also I heard the voice of the Lord saying who shall I send, and who will go for us? Then said I, here am I, send me."




April 01, 2019, 12:41 PM
Harleysbluff
TA31H
April 01, 2019, 03:12 PM
SgtGold
quote:
Originally posted by MikeinNC:
I zero my Ars with iron sights at 1000 inches just like we did in the service. Balistically it’s the same as a 100 yard zero. With a scope I zero at 100 yards


You zero at 83 feet?


_____________________________
'I'm pretty fly for a white guy'.

April 01, 2019, 03:55 PM
Steve in PA
I use the 50 yard zero on my rifles; one with Aimpoint PRO, the other has iron sights.

I also have the officers in my department use the same zero. We qualify out to 100 yards and have no issues with this zero.


Steve
"The Marines I have seen around the world have, the cleanest bodies, the filthiest minds, the highest morale, and the lowest morals of any group of animals I have ever seen. Thank God for the United States Marine Corps." Eleanor Roosevelt, 1945
April 01, 2019, 04:20 PM
MikeinNC
quote:
Originally posted by SgtGold:
quote:
Originally posted by MikeinNC:
I zero my Ars with iron sights at 1000 inches just like we did in the service. Balistically it’s the same as a 100 yard zero. With a scope I zero at 100 yards


You zero at 83 feet?


Yup, Click here

We used that for marksmanship and to zero the rifle to that shooter and it is the same as using a 100 yard zero.

The things you have to do when you do not have access to a real military known distance range.



"Violence, naked force, has settled more issues in history than has any other factor.” Robert A. Heinlein

“You may beat me, but you will never win.” sigmonkey-2020

“A single round of buckshot to the torso almost always results in an immediate change of behavior.” Chris Baker
April 01, 2019, 04:24 PM
Ryanp225
I like the 50 yard zero myself. Acceptably clean shots out to 300 on center mass without having to remember what the holdover is. Even I can handle that.