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Thread: Sighting in at short ranges

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    Sighting in at short ranges

    Ok im not sure if this the right place in the hide to ask but here goes. The weather is aweful and i want to resight 2 ar's one with eotech and one with a leupold vx-r 1.25-4x20 and a bolt .308 with a leupold 6.5-20x50 mk4. How do i sight in at say 25 yards? I have no problems sighting in at 100 or 500(.338 lapua) but 25 ive never done. Thanks guys.
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    Re: Sighting in at short ranges

    You sight-in the same way. The value of the adjustments change accordingly.

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    Re: Sighting in at short ranges

    So what do you want the zero to be?

    Do you have a ballistic program?

    Run the program for your load with all the sight to bore offset and relevant info.

    Read how high or low your round will be at 25m for the specific zero you want. Keep your point of aim but you want your rounds to strike at the desired offset.


    So for example, if i want a 300 meter zero and i know at 25m my round is 1.5 inches below my point of aim, when I use the 25m range I will aim center of my target but adjust my rounds onto my 1.5 inches mark below my point of aim. I just zeroed for my 300m.

    All the numbers used were just made up to demonstrate how it is done.

    Hope this explained it.
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    Re: Sighting in at short ranges

    It would help us help him if he gave us a more specific question than 'How do I sight-in at 25 yards?' I answered that question.

    He didn't say whether he wanted to zero for a particular disance while inside of his zero range. If so, he needs to know that the elevation zero is comprised of two parts: First, compensation for the bullet drop from the muzzle to the zero-range (for example, 100 yards / with a .308 that drop is about 2.7 inches, or 2.6 MOA or .75 Mils). Second, the mechanical offset of the line of sight over the line of the bore (assume a sight height of 1.75 inches, which at 100 yards is about 1.7 MOA or .5 Mils). In the example I gave, one would add those two up: 4.3 MOA or about 1.25 Mils. That's the 100 yard zero on my .308.

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    Re: Sighting in at short ranges

    OP are you wanting to rezero the rifles as in zero scope knobs and use 25 yards as your starting point in dialing in data so now 25 yards are the rifles' new zero or are you just trying to dial 25 yard data in to shoot closer? They are different operations.

    Graham gave some good numbers for 25 yard data from a 100 yard zero. It's dependent on scope above bore height but those numbers will get you close.

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    Re: Sighting in at short ranges

    I am limited to about 25yds for a few days and am bored and want to redo some of my gear and i have a rifle i just got back from yhm(so they could check rifle and suppressor to find out why i had a baffle strike) and need to get scope back to close to zero. I had a buddy say just zero at 25yds and adjust accordingly to what ever zero u want to end up with. I just am not sure how to do it. I want 100yd zero on ar's and the .308 and a 500yd zero on .338 lapua. Like i said i jave no prob zeroing up like 100 to 500 but going down to 25 i dont know if i zero to 25 and multiply that # by4 to get 100 yd zero. Thanks for thw help. Ive just never done this and want to do it correctly and not have some jackwad make fun of me an say something stupid.
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    Re: Sighting in at short ranges

    Originally Posted By: aussiegolf
    I had a buddy say just zero at 25yds and adjust accordingly to what ever zero u want to end up with... I want 100yd zero on ar's and the .308 and a 500yd zero on .338 lapua.
    So you want to get a 100 yard zero (and a 500 yard zero), but to obtain that zero at 25 yards?

    And to attempt all this while using English as your second language. [img]<>/wink.gif[/img]

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    Re: Sighting in at short ranges

    for an AR - sight in at 25 meters ( 82 feet) NOT 25 YARDS this will be damn close to being zeroed at 300 yds - take it from there
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    Re: Sighting in at short ranges

    Originally Posted By: aussiegolf
    I am limited to about 25yds for a few days and am bored and want to redo some of my gear and i have a rifle i just got back from yhm(so they could check rifle and suppressor to find out why i had a baffle strike) and need to get scope back to close to zero. I had a buddy say just zero at 25yds and adjust accordingly to what ever zero u want to end up with. I just am not sure how to do it. I want 100yd zero on ar's and the .308 and a 500yd zero on .338 lapua. Like i said i jave no prob zeroing up like 100 to 500 but going down to 25 i dont know if i zero to 25 and multiply that # by4 to get 100 yd zero. Thanks for thw help. Ive just never done this and want to do it correctly and not have some jackwad make fun of me an say something stupid.


    With all due respect, take the few days during which you are limited to 25 yards, and rather than shoot, read Graham's posts in this thread. Then take as much time and do as much research as necessary to figure out the meaning and value of the information contained therein. Once you TRULY understand what he is saying, then you are ready to go back to the range.

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    Re: Sighting in at short ranges

    Here's ome good reading with charts for the AR. Just decide on what option is best for you and run with it.

    http://www.ar15.com/forums/t_3_18/512335_.html
    GET IN YOUR BUBBLE!

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    Re: Sighting in at short ranges

    Originally Posted By: George63
    for an AR - sight in at 25 meters ( 82 feet) NOT 25 YARDS this will be damn close to being zeroed at 300 yds - take it from there
    With all due respect, 'damn close' isn't a zero. We do not engage targets with only a probability of hitting them.

    You are attempting to describe the Army 25/300 meter zero. With this zero, at 200 meters, a .223 will be about 13” above line of sight with their ammo. The Marine Corps recommends a 36 yard zero, resulting in a maximum rise above the line of sight of 9”. This is a 'battle zero' and it does not adapt well to either CQB or to precision work.

    Originally Posted By: 19Scout77
    Once you TRULY understand what he is saying, then you are ready to go back to the range.
    That's good advice. [img]<>/wink.gif[/img]

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    Re: Sighting in at short ranges

    I would simply say to be patient.

    There are some pretty crucial variables, like sight axis height above bore line, that will tend to make anything you try to do on a 'quick an dirty' basis produce some pretty inexact results.

    At 25 yards, you can shoot, see, and correct onto target anyway, but none of what you end up with will be 'deadnuts on' for the extended distance.

    Wait, do it once, do it right.

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    Re: Sighting in at short ranges

    'damn close' isn't a zero.



    it means you will not need to start at 100 or 200 - on an iron sights AR or with optics mounted similar height you san zero at 82 ft and go straight to a 300 yd target for final adjustments - isn't that pretty much the definition of "damn close" ?

    there was little reason to go into great detail as the OP was unlikely to listen any way - and all the other replies were going to have him chasing his tail more than he already was

    some people need a short, simple explanation - that is what I gave
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    Re: Sighting in at short ranges

    ok maby im not getting across very clearly what i am trying to accomplish. is there a way to zero at 25yards (because yards is what i use) and then calculate how many moa i need to move my turrets to get 100 yard hits. then i can go to the range and correctly like everyone of you do, go thru the process of getting true zero. i wasent looking for smartass comments, i was looking for answers.
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    Re: Sighting in at short ranges

    Originally Posted By: aussiegolf
    ok maby im not getting across very clearly what i am trying to accomplish. is there a way to zero at 25yards (because yards is what i use) and then calculate how many moa i need to move my turrets to get 100 yard hits. then i can go to the range and correctly like everyone of you do, go thru the process of getting true zero. i wasent looking for smartass comments, i was looking for answers.
    If you are shooting no farther than 100 yds you will be hitting a target from a 25 yd zero. If you zero dead on at 25 yds you probably will only be hitting about 3" high at 100. Youwon;t be far off. Good luck
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    Re: Sighting in at short ranges

    thanks
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    Re: Sighting in at short ranges

    Originally Posted By: RobertB
    Originally Posted By: aussiegolf
    ok maby im not getting across very clearly what i am trying to accomplish. is there a way to zero at 25yards (because yards is what i use) and then calculate how many moa i need to move my turrets to get 100 yard hits. then i can go to the range and correctly like everyone of you do, go thru the process of getting true zero. i wasent looking for smartass comments, i was looking for answers.
    If you are shooting no farther than 100 yds you will be hitting a target from a 25 yd zero. If you zero dead on at 25 yds you probably will only be hitting about 3" high at 100. Youwon;t be far off. Good luck


    1.6" low @ 25y = 100y z
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    Re: Sighting in at short ranges

    thats what i came up with (-1.6) shooting 69gr and -0.8 with 55gr. now on to .300blkout, and .308. thanks for the honest help. i think i have it figured out now.
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    Re: Sighting in at short ranges

    aussiegolf

    What you need is one of these:




    It's a calibrated 25yd zero target for 144gr and 155gr 7.62mm.

    Drill is: Hang it dead level at 25 yds (use a plumbline if needed), sight to the centre of the bull and fire. Then adjust your elevation (and windage) to the required zero level. 25yds zero = smack in the centre, if you want further aim at the centre but the shot should break the vertical scale at the required height. Verify at full distance. Done.

    Sadly I don't have one for 5.56mm.

    But it shouldn't be too hard to sort out your own if you load the necessary data into something like Shooter?. For reference this is an MOA version. In real size the elevation scale is marked upwards in 1" (4MOA in this scale) divisions, the windage scale are 1/4" divisions (1MOA) - easy maths seeing it's for 1/4 distance

    Apologies for the rough join at 1000....my scanner isn't up to doing it in one go.


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    Re: Sighting in at short ranges

    thanks for the help
    ,,