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Discussion Starter · #1 ·
I am new to the world of using optics so I figured I would ask if there was any tricks to boresighting for the first time?

I just picked up this scope from Midway to learn how to use glass/mildot systems: http://www.midwayusa.com/Product/12...e-6-18x-40mm-side-focus-mil-dot-reticle-matte


I already have a laser boresight I used to get my aimpoint into the general area. Is it essentially the same process?

I will have this scope mounted on my Mod 0 EBR, w/ a LaRue mount LT-608 w/ low rings (cheapies)

I plan on starting at the 100 to zero, then take it to the 300 to experiment with the variable focus powers that are available. This is all new to me.
 

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If everything were perfect then starting at 100 yards might be OK but nothing is ever perfect.

  • Put up a target at 25 yards and create an aim point that is as small as your scope will resolve.
  • Fire your first round.
  • Aim that same point of aim.
  • While continuing to aim at that original aim point, adjust the scope so that the cross hairs move to the center of the point of impact from the first round. Do not allow the rifle to move while you make this adjustment. You are simply adjusting the scope so that it coincides with where the bullet impacts.
  • Now fire a second shot at the 25 yard target and you should be dead on, if not make any minor adjustment that you have to.
  • After you are on at 25 try a round at 50 yards or just take it out to 100. If you fire a shot at 100 then you will probably be a couple inches low. Make the necessary adjustment.

If you follow this process and your scope is properly aligned with the bore, you will rarely use more than four or five shots to get zeroed.
 

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Discussion Starter · #3 ·
So I don't have my owners manual yet. But I'm assuming when you move the POA to the POI you are using windage and elevation. Do you zero out the knobs afterwards like when you calibrate the rear sights? Is there any purpose of zeroing at. Specific distance like the 200 or 300 after the initial boresight at 25yrds? Should it be done at a specific power?
 

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Yup, use the windage and elevation to bring the POA to the POI.

If the knobs are designed so that you can loosen them and then set them at zero then yes, you would do that after the rifle hits your POA at the particular range you want.

You zero the rifle at what ever range you feel works best for your purposes. Let me give you a couple of examples.

Usually most people that shoot at targets will set the scope for 100 yards and then zero the knobs. Then you can use either the mil dots for longer ranges or adjust the knobs for the appropriate "come-ups".

Hunters usually like to set the scope for a zero based on the maximum point blank range for the cartridge being used. Then you would use the mil dots or adjust the scope for any range other than what the scope is zeroed for.

I don't know if you are familiar with the concept of "Point Blank Range" (PBR) but basically the concept is that if you have a target that is 6 inches in diameter then you would use the range where the bullet drops 3 inches below the POA as your PBR. This way the bullet will normally not go any higher than 3 inches above the POA or 3 inches below it out to the PBR. So theoretically you don't need to change the scope until the target is past the PBR.


So I don't have my owners manual yet. But I'm assuming when you move the POA to the POI you are using windage and elevation. Do you zero out the knobs afterwards like when you calibrate the rear sights? Is there any purpose of zeroing at. Specific distance like the 200 or 300 after the initial boresight at 25yrds? Should it be done at a specific power?
 

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Discussion Starter · #5 ·
solid intel, thanks man I appreciate it.


I will start out at zeroing at the 100 since I will be doing only target shooting for now, and then do some dry runs making adjustments out to the 300. I am guessing there wont be too much of an adjustment needed at those ranges, but it may teach me how to practice the hold overs if I don't want to change the dope. I am assuming it doesnt matter what power you zero at as much as how you are acquiring targets at a certain distance anyways. I will probably miss paper the first clip anyways :) thanks again!
 

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I forgot to mention that if your scope is variable powered then yes, it does matter what power you are on when you use the mil dots. There will be a specific power that must be used in order to have the mil dots properly calibrated. Usually that's the highest power but you should verify that with the manufacturer's info. You can also test it by checking the spacing between the mil dots at 100 yards.

At 100 yards the mil dots are spaced at 3.6 inches, so make a couple of marks 3.6 inches apart on your target, large enough to see through the scope at a range of 100 yards. Post your target and then go to your 100 yard firing position. Look through the scope and adjust the magnification until the dots are centered on the 3.6 inch marks. Whatever magnification you are on will be the magnification you should use whenever you are working with the mil dots.
 

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solid intel, thanks man I appreciate it.


I will start out at zeroing at the 100 since I will be doing only target shooting for now, and then do some dry runs making adjustments out to the 300. I am guessing there wont be too much of an adjustment needed at those ranges, but it may teach me how to practice the hold overs if I don't want to change the dope. I am assuming it doesnt matter what power you zero at as much as how you are acquiring targets at a certain distance anyways. I will probably miss paper the first clip anyways :) thanks again!
After your zero'd for 100yards your come up for 300 depending on your scope height and ammo selection should be about 1.3mils or so (Make sure if your scope is a SFP your set to the right power setting to use the dots for your come ups). For me offhand I believe it is 1.4mils with 168gr match. That is roughly 20 clicks up elevation if your scope is 1/4" at a 100yards. That will get you on paper pretty close. Fine adj for your needs and conditions.
 

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Discussion Starter · #8 ·
okay,so if I understand this correctly, almost everyone "zeros" the scope at 100yrds at max power unless the manufacturer requests other wise.

Then, sounds like most shooters prefer to use the mildot's to adjust their POI with a hold over method vs just changing it directly on the scope itself?

But some will tweek their scopes to known distances since the data would be roughly the same regardless of what they are shooting at for target at 100,200-700yrds etc. for example...lets say I know that I need to bring it up 20 inches due to the BCD for the round I am using from the 300-400, I can just estimate with the Mils OR put the clicks up 20-24 using my scopes 1/8 MOA adjustments to get near the target.

so it would sound like the more proficient shooters like to just use the mildots since they have the practice behind them and only utilize the MOA when the environment calls for them to slow down and find a general area.

My knobs adjust at 1/8 MOA (not the standard I know)

So do these sound right for adjustments made directly on the scope itself?

Yards
100 - 1 click = 1/8 inch
200 - 1 click = 1/4 inch
300 - 1 click = 1/2 inch
400 - 1 click = 3/4 inch
500 - 1 click = 1 inch
600 - 1 click = 1 1/8 inch

Thanks guys.
 

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Everyone has their own preference so I can't really say what the most common way is but it is a good way to start out; it helps make things simpler until you get the hang of using the mil dots.

The way I use a mil dots depend on what kind of shooting I'm doing. If I am shooting at paper then I use the knobs to adjust my aim point for elevation and I may or may not use the knob adjustment for the windage. If I take a shot at a animal and I see that my point of impact was 1 mil low and a half mil to the right I will use the mil dots to change my POA so that I can make a quick follow up shot rather than taking the time to adjust the knobs.

As for how many clicks you adjust at any particular range, well that requires a little math. Your scope knobs are setup for 1/8 MOA per click. One MOA is equivalent to a different number of inches at different ranges but the change in inches is linear, there is a specific amount of change for a specific distance.

1 MOA at 100 yards is approx. 1 inch (closer to 1.05")
1 MOA at 200 yards is approx. 2 inches
1 MOA at 300 yards is approx 3 inches
and on and on...

So at 600 yards one MOA is about 6 inches (it's actually closer to 6.28 inches but we can round off unless you are shooting for score).

Your scope is setup so that you have 8 clicks for one MOA, regardless of what the range is.

So at 100 yards 1 MOA is one inch, divide one inch by the 8 clicks it takes to move one MOA and that means each click is equivalent to 1/8 inch at 100 yards.

At 600 yards 1 MOA is about 6 inches, divide 6 inches by the 8 clicks it takes to move one MOA and that means that each click is equivalent to about 3/4 inch at 600 yards.

So;

Yards
100 - 1 click = 1/8 inch
200 - 1 click = 1/4 inch
300 - 1 click = 3/8 inch
400 - 1 click = 1/2 inch
500 - 1 click = 5/8inch
600 - 1 click = 3/4 inch

There is an easy way to remember this.
100 yards = 1/8 inch
200 yards = 2/8 inch
300 yards = 3/8 inch
400 yards = 4/8 inch
500 yards = 5/8 inch
600 yards = 6/8 inch

Notice the correspondence between the first number in the range and the numerator of the fraction (the top number of the fraction). That makes it easier to figure out the number of inches per click at weird ranges. A range of 732 yards would mean that each click is equivalent to 7.32/8 of an inch. At 1000 yards each click is equal to 10/8 of an inch or about 1.25 inches per click.

So if you are zeroed at 100 yards and your target is 450 yards away you know that each click is 4.5/8 of an inch, that's just little more than a half inch per click. If you need to compensate for a 20 inch drop then you would need to add something less then 40 clicks, maybe around 30 to 35 clicks.

You can sit down and do the math or just guess like I just did, with practice you will become familiar with your weapon, scope, and cartridge and that guesstimate of 30 to 35 clicks will get more precise. I recommend to always add a little less adjustment then you calculated because most scopes don't track perfectly and you can always adjust a little with a different POA.


okay,so if I understand this correctly, almost everyone "zeros" the scope at 100yrds at max power unless the manufacturer requests other wise.

Then, sounds like most shooters prefer to use the mildot's to adjust their POI with a hold over method vs just changing it directly on the scope itself?

But some will tweek their scopes to known distances since the data would be roughly the same regardless of what they are shooting at for target at 100,200-700yrds etc. for example...lets say I know that I need to bring it up 20 inches due to the BCD for the round I am using from the 300-400, I can just estimate with the Mils OR put the clicks up 20-24 using my scopes 1/8 MOA adjustments to get near the target.

so it would sound like the more proficient shooters like to just use the mildots since they have the practice behind them and only utilize the MOA when the environment calls for them to slow down and find a general area.

My knobs adjust at 1/8 MOA (not the standard I know)

So do these sound right for adjustments made directly on the scope itself?

Yards
100 - 1 click = 1/8 inch
200 - 1 click = 1/4 inch
300 - 1 click = 1/2 inch
400 - 1 click = 3/4 inch
500 - 1 click = 1 inch
600 - 1 click = 1 1/8 inch

Thanks guys.
 

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Discussion Starter · #10 ·
Okay, maybe you can give me a good answer here. I just mounted the scope to my weapon and obviously the next step is boresighting it. I am not sure what the vertical numbers on my elevation mean on the bottom part of the turret. I know the lines in white going horizontally are my MOA clicks (1/8.) The factory setting came at 0 which completely bottomed it out. Which means if I wanted to make adjustments, in theory I would have bottomed out of elevation and not able to go lower right out of the box. Do you know what the witness lines mean that are in the pillar in the center? they go from left to right alternating: 0, 1, 2, 3, 4, 5, 6, 7. Then I run out of elevation. Same is for the windage.

When it comes to a proper boresight shouldnt I start somewhere in the middle of both knobs (like the 3?) so I have the flexibility to keep adjusting? Then I can loosen the set screws and zero it out completely once its on target, and then retighten them? Here is a picture of what I am looking at. There are no damn instructions with the scope that make sense to me.

[/IMG]
 

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Discussion Starter · #12 ·
thanks. I appreciate you taking all the time to help. So I see its called the index ring. What is the purpose of an index ring? just to be a reference when you put your settings on at different distances and write them down? Any suggestion where the knobs should be on index ring at the beginning step of boresighting?
 

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Yes, the index ring is just a reference, once the rifle is zeroed keep track of the value that the grip and index represent. It looks like you don't have the ability to re-calibrate your knobs so that they read zero after you sight the rifle in. In other words, after sighting the rifle in, the grip will have exposed a certain number of lines on the index and the grip itself will be turned past the zero mark a certain number of graduations. The combination of the two will be the number reference that represents your zero point.

The lines probably represent one full turn of the grip. Note that the each mark on the grip represents one click or 1/8 MOA. I'm not sure how many MOA you have per turn but it looks like only 6, in other words the marks on the grip go from 0,1,2,3,4,5, and back to 0. That has me a little confused, that means that you only move 6 MOA per turn and you have 7 turns so that's a total of 42 MOA. But the specs say you have 50 MOA travel. I'll bet that you can turn the grip up past the line marked 7 a little. If so then that would be the remaining 8 MOA that the scope should travel. You'll need to check that out yourself because there should be a total of 50 MOA of travel in the knobs.

So let's say that after zeroing the rifle at 100 yards the grip is situated so that the second index line is showing (you turned two turns up on the elevation) and you went 17 clicks past the zero mark on the grip (that would be one mark past the two on the grip). You would record that on a range card as your 100 yard zero for that cartridge, something like 100= 2-17. Now you want to hit a target at a different range and you have to raise the impact by 5 MOA. That would require 5 times 8 clicks or a total of 40 clicks of elevation. You can either turn the grip and count out 40 clicks of up elevation or, knowing that each turn of the grip equals 48 clicks (6 increments on the grip times 8 clicks per each increment), just add one full turn of up elevation and then back off 8 clicks (add up elevation so that the third line is exposed on the index and the grip is at one click past the two and then turn the grip back 8 clicks). There are any number of ways that you can do the math but find a way that makes sense to you and do it the same way every time. Build the muscle memory so that you don't mess up the adjustment when you are in a hurry.
 

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Discussion Starter · #14 ·
awesome feedback. I bet you thought the next thing I was gonna ask you was if you could come out here and show me how to load it and clean it too huh? :) really appreciate you taking the time to explain because using glass is a new thing for me I am eager to learn. I am just going to put this sucker on the 1 index to see where I am hitting between the 50-100yrds line starting out, then make the adjustments needed to find my zero and write it down. I also think that it may just be better (for learning purposes) to keep my dope on the scope at 100yrds, and then teach myself how to use the Mildot up to the 300yrd line without changing the knobs. If I need to adjust, no biggie, but I can see the real skill is being able to make shots "on the fly" and practicing good shooter basics. Thanks again man!! Semper
 

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Not a problem, glad to help, as long as everything I said works out when you test things at the range; but I'm pretty sure I have it all right even though I've never worked with that particular model scope. Most scopes use the same concepts, you just have to get used to the specific knobology and such. I think your plan sounds like a good starting point.
 
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