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posted
https://youtu.be/jttB1kUXfJE

Thoughts? I did the 25 meter zero but I'm thinking this might be better.
Good info here.


I'd rather be hated for who I am than loved for who I'm not.
 
Posts: 2079 | Location: The armpit of Ohio | Registered: August 18, 2013Reply With QuoteReport This Post
Go ahead punk, make my day
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To me, zeros really depend on your environment, typical shooting distances, and needs.

Personally I never liked the 25 yard zero, since it changes POI quickly from 25-200 and has holdovers and unders.

I can see the utility in 36-50-100 yard zeros and for me, the 100 yards is what I use, since it's very hard to get a shot >200 yards where I am and even past that, it's all holdover (never hold unders).
 
Posts: 40392 | Registered: July 12, 2008Reply With QuoteReport This Post
Rule #1: Use enough gun
Picture of Bigboreshooter
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Supposedly a 50 yd zero will have you back around zero at 200. I have found this to be pretty much the case with my bulk range loads in all of my AR’s (55gr fmj at 2,800-2,900 FPS). These loads are around 1.5” high st 100. This setting allows a dead-on hold out past 250 yards.



When a strong man, fully armed, guards his own house, his possessions are undisturbed. Luke 11:21


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Either you are with us, or you are with the terrorists." -- George W. Bush

 
Posts: 14430 | Location: Birmingham, Alabama | Registered: February 25, 2009Reply With QuoteReport This Post
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quote:
Originally posted by RHINOWSO:
To me, zeros really depend on your environment, typical shooting distances, and needs.

Personally I never liked the 25 yard zero, since it changes POI quickly from 25-200 and has holdovers and unders.

I can see the utility in 36-50-100 yard zeros and for me, the 100 yards is what I use, since it's very hard to get a shot >200 yards where I am and even past that, it's all holdover (never hold unders).


I never liked the hold unders either, just never made sense to me.
I don't really have any needs for my AR and typical distance is 50 yards or under. I don't hunt with it and I have different protection for my house.
It's kind of a range rifle for fun. I didn't change anything out and the only accessories are an EOTech and a sling mount.
I do get where he's coming from in the video though.


I'd rather be hated for who I am than loved for who I'm not.
 
Posts: 2079 | Location: The armpit of Ohio | Registered: August 18, 2013Reply With QuoteReport This Post
We gonna get some
oojima in this house!
Picture of smithnsig
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Depends on the optic. I have a vortex Razor that has the JM1 reticle. I zero at 50 and then tweak it to 200. The 50 yd zero gets me real close. It has a BDC that is designed for a 200 yd zero.

I have a Leupold VXR 3-9 that has a BDC turret that is designed for a 100 yard zero.

I have a Leupold VXR Hog 1.25-4 that I zero at 50 that will put me close all the way to about 225.
It has BDC hashes but I haven’t run them or shot them.

I have a Holosun 510C that is close at 50.


-----------------------------------------------------------
TCB all the time...
 
Posts: 5925 | Location: Cantonment/Perdido Key, Florida | Registered: September 28, 2009Reply With QuoteReport This Post
Freethinker
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I have had lots of experience with using and mandating 50 yard zeroes for myself and trainees, but at least one shooter I know well prefers a 25 yard zero. It doesn’t make a huge difference at close distances because the trajectories are similar, but for engagements out to 200 yards, it seems the people with 50 yard zeroes have less trouble. And of course, a 50 yard zero is very close to a 200 yard zero with many 223/5.56 loads. Some people favor the 25 yard (or, more properly 25 meter) zero because that’s what the U.S. military usually dictates because of their engagements that extend much farther out than what police can expect.

I am also not a fan of using something like the bottom of the EOTech reticle circle as an aiming aid for close distance, fast engagements. With a 50 yard zero, sighting offset is still necessary at 15, 25 yards, and beyond for precision shots on small targets, but it varies with distance. I therefore just adjust my point of aim on the target with the single Aimpoint dot based on the target distance.

But zeroes are easy to adjust. Different circumstances can affect what’s best for the individual. If you’re not happy with one, try another.




“Most men … can seldom accept the simplest and most obvious truth if it … would oblige them to admit the falsity of conclusions … which they have woven, thread by thread, into the fabrics of their lives.”
— Leo Tolstoy
 
Posts: 38773 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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quote:
Originally posted by sigfreund:
I have had lots of experience with using and mandating 50 yard zeroes for myself and trainees, but at least one shooter I know well prefers a 25 yard zero. It doesn’t make a huge difference at close distances because the trajectories are similar, but for engagements out to 200 yards, it seems the people with 50 yard zeroes have less trouble. And of course, a 50 yard zero is very close to a 200 yard zero with many 223/5.56 loads. Some people favor the 25 yard (or, more properly 25 meter) zero because that’s what the U.S. military usually dictates because of their engagements that extend much farther out than what police can expect.

I am also not a fan of using something like the bottom of the EOTech reticle circle as an aiming aid for close distance, fast engagements. With a 50 yard zero, sighting offset is still necessary at 15, 25 yards, and beyond for precision shots on small targets, but it varies with distance. I therefore just adjust my point of aim on the target with the single Aimpoint dot based on the target distance.

But zeroes are easy to adjust. Different circumstances can affect what’s best for the individual. If you’re not happy with one, try another.


Not a fan of using the bottom either and that's one thing I disagree about in the video.
I just finished a 36 yard zero with the AR about half an hour ago. Have to say that it wasn't much different than the 25 meter zero I had on it. I had to make zero adjustments.
It's a beautiful day with the weather right now so I took advantage with the Glock and AR.


I'd rather be hated for who I am than loved for who I'm not.
 
Posts: 2079 | Location: The armpit of Ohio | Registered: August 18, 2013Reply With QuoteReport This Post
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Former Army here - we did the 25 / 300 back in the day

but IMO the 50 / 200-ish makes more sense

-----------------------


Proverbs 27:17 - As iron sharpens iron, so one man sharpens another.
 
Posts: 6986 | Location: Florida | Registered: September 20, 2004Reply With QuoteReport This Post
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quote:
Originally posted by Sig209:
Former Army here - we did the 25 / 300 back in the day

but IMO the 50 / 200-ish makes more sense

-----------------------


Same here but different branch. That's why I did it because that's how I was instructed.
Ran across the video and decided to change up.


I'd rather be hated for who I am than loved for who I'm not.
 
Posts: 2079 | Location: The armpit of Ohio | Registered: August 18, 2013Reply With QuoteReport This Post
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Picture of onpointgun
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For a rifle with a red dot type of optic this is my favorite zero.


I will be swift in my attack. My venom is packed with enough pride and gun powder to take down
any adversary that attempts to tread on my freedom. You've been warned, but if you
still want to test me, take a step forward.
 
Posts: 1854 | Location: ON THE YELLOW BRICK ROAD | Registered: February 11, 2009Reply With QuoteReport This Post
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The expected shooting distances and the type of sight should be primary factors in determining the optic's zero. Here are some flight comparisons for various zeros. Distances in yards, POI height above (+) or below (-) POA in inches, muzzle velocity of 3000 fps, Sierra 55 grain FMJ, 3000 foot Density Altitude, 2.5" sight-over-bore height, per JBM.

25 yard zero
25 yds 0"
50 yds +1.4"
75 yds +4.2"
100 yds +5.9"
150 yds +8.4"
200 yds +9.5"
250 yds +9.0"
300 yds +6.8"
peak height of +9.5" at 200-220 yds
second zero at 375 yds

36 yard zero
25 yds -.7"
50 yds +.8"
75 yds +2.1"
100 yds +3.1"
150 yds +4.1"
200 yds +3.8"
250 yds +1.9"
300 yds -1.7"
peak height of +4.2" at 160-165 yds
second zero at 280 yds

50 yard zero
25 yds -1.1"
50 yds 0"
75 yds +.9"
100 yds +1.4"
150 yds +1.6"
200 yds +.5"
250 yds -2.2"
300 yds -6.6"
peak height of +1.7" at 120-145 yds
second zero at 210 yds

100 yard zero
25 yds -1.5"
50 yds -.7"
75 yds -.2"
100 yds 0"
150 yds -.5"
200 yds -2.4"
250 yds -5.8"
300 yds -10.9"

As target distances increase, the gnat's ass measurement differences aren't that important if one is shooting from unsupported positions with an unmagnified optic. What is important is the shooter's understanding of the flight ballistics of their own rifle/optic/ammo at given distances.
 
Posts: 5622 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
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what are you shooting, with what optic, with what load, at what distance. I'm amazed at the zero discussions. It simply doesn't matter as you are going to have to adapt to your situation no matter what. I happen to prefer a 50y zero because it works the best in the ranges that I am likely to use, with the ammo I am using and the targets I am trying to hit. But in just about every case I have to adopt some change to the POA/POI to deal with the situation (primarily when the targets are close).
No magic, really.


“So in war, the way is to avoid what is strong, and strike at what is weak.”
 
Posts: 7326 | Registered: October 14, 2004Reply With QuoteReport This Post
Sigless in
Indiana
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200 for for most purposes.


I use 100 for my longer range AR because it fits well with that reticle and gives me a clean, round number dope card.
 
Posts: 13239 | Location: The Edge of the Ozarks | Registered: December 04, 2003Reply With QuoteReport This Post
fugitive from reality
Picture of SgtGold
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quote:
Originally posted by Sig209:
Former Army here - we did the 25 / 300 back in the day

but IMO the 50 / 200-ish makes more sense

-----------------------


After 15+ years of doing it the Army way my brain is conditioned to the hold over/under of the 25/300. The 50/200 is quite popular with certain SOCOM units because they train like they fight. YMMV.


_____________________________
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Posts: 5956 | Location: Newyorkistan | Registered: March 28, 2007Reply With QuoteReport This Post
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Picture of Ryanp225
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I'm a big fan of the 50/200 zero for my needs.
With that setup I can get pretty dang good hits out to 250 yards without really worrying about the distance and offset.
 
Posts: 7466 | Location: Colorado | Registered: January 04, 2009Reply With QuoteReport This Post
Freethinker
Picture of sigfreund
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Some figures using Applied Ballistics solver and the M855 bullet fired from 14.5 inch M4 barrel using a 25 meter zero. Iron sight height or absolute co-witnessed optical sight (2.5 inches). G7 ballistic coefficient 0.153 with muzzle velocity of ~2920 fps. “Standard” sea level atmospheric conditions.
Table is in meters, which is the usual US military practice.

25 m (27.3 yd): 0
50 m (54.7 yd): + 2.2"
75 m (82.0 yd): + 4.1"
100 m (109.4 yd): + 5.9"
150 m (164.4 yd): + 7.5"
200 m (218.7 yd): + 7.6"
250 m (273.4 yd): + 5.7"
300 m (328.1 yd): + 1.6"
314 m (343.4 yd): 0




“Most men … can seldom accept the simplest and most obvious truth if it … would oblige them to admit the falsity of conclusions … which they have woven, thread by thread, into the fabrics of their lives.”
— Leo Tolstoy
 
Posts: 38773 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
Age Quod Agis
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Before I had a BDC scope on it, I did the 50-200 zero. Now, I do a 100 because of the optic.



"We may consent to be governed, but we will not be ruled." - Kevin D. Williamson, 2012

"All the citizens of this land are of right freemen; they owe no allegiance to any class and should recognize no task-masters. Under the chart of their liberties, under the law of high heaven, they are free and without shackles on their limbs nor mortgages upon the fruits of their brain or muscles; they bow down before no prince, potentate, or sovereign, nor kiss the royal robes of any crowned head; they render homage only to their God and should pay tribute only to their Government. Such at least is the spirit of our institutions, the character of our written national compact."

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Posts: 9531 | Location: Central Florida | Registered: November 02, 2008Reply With QuoteReport This Post
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I have mine set up with a Nikon p223 scope with a bdc reticle on a Burris PEPR mount. I also use a 100 yard zero. In my opinion it is nice to know your bullet will hit low out to 150 yards (except at 100 yards)then use the scope reticle for the rest, and to be perfectly honest I haven't shot mine over 100 yards yet due to my work schedule and weather conditions.
 
Posts: 1694 | Location: U.P. of michigan | Registered: March 02, 2010Reply With QuoteReport This Post
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quote:
Originally posted by hvyhawler:
I have mine set up with a Nikon p223 scope with a bdc reticle on a Burris PEPR mount. I also use a 100 yard zero. In my opinion it is nice to know your bullet will hit low out to 150 yards (except at 100 yards)then use the scope reticle for the rest, and to be perfectly honest I haven't shot mine over 100 yards yet due to my work schedule and weather conditions.


it is interesting how close .223 and .308 trajectories are at closer ranges (under 400yds for example)

basically the same for practical purposes

i like that you could place that 100yd zeroed Nikon on a .223 or .308 AR and - in an emergency - not have to re-zero it

------------------------------------


Proverbs 27:17 - As iron sharpens iron, so one man sharpens another.
 
Posts: 6986 | Location: Florida | Registered: September 20, 2004Reply With QuoteReport This Post
Go ahead punk, make my day
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quote:
Originally posted by Sig209:
i like that you could place that 100yd zeroed Nikon on a .223 or .308 AR and - in an emergency - not have to re-zero it

Good luck with that...

Yes, they might have the same general trajectory if fired out of the same rifle with an identically installed barrel, but you have no idea if the zero between rifles is remotely the same.

Don't believe me? Take 5 AR15s, zero an optic on one, then move it to the other 4. You'll likely see impacts all over the place from rifle to rifle.

I have seen impact changes simply by moving an optic forward or back on the same rifle while getting eye relief spot on.
 
Posts: 40392 | Registered: July 12, 2008Reply With QuoteReport This Post
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