Help me figure out my zero problems

[reapur]

Hello,
I have an AR15 with a red dot, both a holosun 503c and eotech xps3.

I've been consulting ballistics calculators from Federal, Hornady and Sterlok pro on my phone.
I'm pretty sure I have a the ballistics for the M855 figured out since it's available all over the internet and strelok pro has it in its database.



So According to these calculators for a 200 yard zero, it should look like the above picture.
The way I see it, I can zero at 25 yards if I when I aim at the bullseye, I let it shoot 1" high, right?
Then at 50 POI should be almost right at POA, just .3 off.

Well I went out today and got the zero at 25 yards, where the POI is 1" high.
Then I went to the 50 yard range, and POI was 6+" high!
I went back to the 25 and it was right on at 1" high, I go back to the 50 and POI is still high.

How is this supposed to work?

Thanks

[00tec]

Anything between 25(ish) yards and 200 (ish) yards will be high. 25 and 200 should be close to the same. Everything after 200 will be low.

[crays]

Try this link: http://www.m4carbine.net/showthread....ory-curve-5-56

It's a lot of info in the thread, but read through it several times, and it might help some.

[mattiooo]

This is why chose a 50 yard zero:


This shows the POI from different ranges when POA is the red circle.

This article has a target for setting a 50 yard zero with the target placed at 10 yards. Makes it really easy to dial in. It also has a link to another article with a video that discusses the reasoning.
http://jerkingthetrigger.com/2015/02...o-at-10-yards/

[mattiooo]

Try this link: http://www.m4carbine.net/showthread....ory-curve-5-56

It's a lot of info in the thread, but read through it several times, and it might help some.

That's a great thread.

[crays]

That's a great thread.

And I have those same AD graphics, + more (different barrel lengths and M855 results), and a variety of sight-in targets from another good thread there. The one I posted above was the first one I could find a quick bookmark for.

[Hoser]

I much prefer a 300 yard zero.

300 is where things start to get hard. I want to hold right where I want the bullet to go. At 400 I can aim for the neck and still make a solid COM hit.

Granted most of the targets I shoot are 8-12 inch plates.

Hold bottom of the plate for everything inside 200. Shade the middle for 200-275.

[crays]

I can't even see a 12" plate at 300 yards. LOL


Thank goodness for magnification.

Sent from somewhere

[Irving]

For all the content we have on this site, we don't have many actual shooting related stickies. I hope this becomes one of them. That target diagram is immensely helpful.

[ray1970]

I've always used the 300 yard zero. For me, the 5.56 is strictly for use inside 300 yards anyways. The total "spread" or whatever you want to call it is only eight or nine inches ish so from 25 to 300 yards I can just hold center mass on a torso sized target and squeeze the shot. The spread on the other zeros is somewhere around eighteen inches. That means once you start getting out past 200 yards you better be paying attention or you may miss low.

Just my opinion. Everyone may not agree.