Scopes: MOA, MIL, 1/4" per click - what it means...

This is a discussion on Scopes: MOA, MIL, 1/4" per click - what it means... within the General Firearm Discussion forums, part of the Related Topics category; I looked at the specs for different scopes and found numerous specs for what a 'click' of the turret does. One was 1/4 MOA per ...

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Thread: Scopes: MOA, MIL, 1/4" per click - what it means...

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    Scopes: MOA, MIL, 1/4" per click - what it means...

    I looked at the specs for different scopes and found numerous specs for what a 'click' of the turret does. One was 1/4 MOA per click, one was 1/4" inch per click at 100 yards, and that 100 yards is critical in this spec. Another was 0.1 MIL per click. Another was on a tactical scope that had a spec of 1/2" per click at 100 yards, and again the 100 yards specification is necessary. And yet another with 1/4 and 1/2 MOA clicks. So what does all this mean and how do we use it?

    The following three posts are to explain how the various scope configurations impact sighting in a scope. It will not address range estimation using the reticles. If there is interest in that, I'll do a separate thread about how that works. So here's the first discussion.

    Sighting in a scope spec'd for 1/4" per click at 100 yards.

    The 1/4" and 1/2" @ 100 yards type specs are the most straightforward so that’s a good place to start. The turrets on a scope have detents and each detent or click changes the POI (point of impact) by a specified amount. The numbers, i.e. 1/4" and 1/2", are the amount the POI is changed for one click of the turret at 100 yards. I mentioned earlier that the 100 yards was critical for this method of specifying scope changes. The 1/4" (and 1/2") is only true at 100 yards, but the spec can be used for other ranges, especially 25, 50, 200, etc. It can also be used at any range but the numbers are not as easy to work with.

    There are two ways to determine how many clicks are needed to adjust the POI to the desired POI: one, use a table if you have one or can find one, or two, use some simple calculations.

    For submultiples (25 & 50 yards) and multiples (200, 300, 400, 500, 600 yards) of 100 yards, the numbers are pretty easy to calculate. You can pretty much do it in your head. If the ranges are not submultiples or multiples of 100 yards, the numbers get a bit unwieldy but the same method applies to both – one is just more intuitive and easier.

    Here's an example of how to zero a scope with 1/4" per click at 100 yards using calculations. I'm at the range to sight in a scope at 100 yards. We’ll assume the scope is close enough to be on paper at 100 yards and I’ll talk about what to do if it isn’t later.

    I place my target at 100 yards and fire two or three shots. I find that my group is tight but I’m 2-1/2” low and 1-3/4” to the left. What do I do? I can adjust my scope’s elevation and windage by trial and error by adjusting and shooting until I’ve walked the scope into zero, but that’s time consuming and can take a lot of ammo, especially when both elevation and windage are off. So instead, I’m going to take advantage of my scope’s adjustment clicks and some intuitive math to speed the process up.

    My scope changes the POI 1/4" per click at 100 yards so I just need to determine how many clicks I need to adjust the elevation and windage to zero.

    For the elevation, I’m low by 2-1/2” so I need to divide 2-1/2” by 1/4” per click. That will tell me how many clicks to change the elevation by. An alternative to dividing per se is to realize there are four clicks per inch of elevation, so to get 2 inches, we would need 8 clicks. That would move us up 2”. Then we need two more clicks for the remaining 1/2” for a total of ten clicks and that should put us right on with the elevation. You would get the same thing by dividing 2-1/2” by 1/4” per click.

    Now for the windage. The windage is off by 1-3/4” but we use the very same process. We either divide 1-3/4” by 1/4” or we again realize there are four clicks in one inch and 3 clicks in 3/4” for a total of 7 clicks.

    So with only two or three shots, we’ve theoretically zeroed our scope. All that’s left is to fire two or three shots to verify the correction. If it’s on, we’re done, if it’s not on zero, we fine tune the very same way we did above. But, the first adjustment should zero the scope. Sometimes we mis-measure or miscount clicks, so it’s always good to confirm zero with a couple of shots.

    What about yardages besides the nice, easy, clean 100 yards? Well there are two cases: one where you are at a submultiple or multiple of 100 yards, and two, where you are somewhere in between multiples.

    In preparation for my pig hunt, I knew I wouldn’t be making shots over 50 yards so it didn’t make sense to have my gun sighted in for 100 or 200 yards, so I decided to sight my scoped bolt rifle in at 50 yards and my AR equipped with an Aimpoint Pro at 25 yards.

    If your scope won't shoot on paper at 100 yards and you want to zero it for 100 yards, you can start at 50 yards or even 25 yards and move the target out after you zero at these shorter ranges - that should get the POI on the paper at 100 yards. This is the method you'd use:

    I set up my target at 50 yards and fired two shots and had a tight group, but the group was low by about 2-1/2” and wide by about 2” (the scope had only been bore sighted). So now, at 50 yards, with a 1/4” per click scope, I have to calculate clicks just a bit differently. One click at 100 yards would move the POI by 1/4”. Since 50 yards is one-half of 100 yards, my click value will also be half as much, or 1/8” per click at 50 yards. From here, it’s the same process as before – determine the clicks, make the adjustments and fire two or three verification shots.

    So for elevation I need to go up by 2-1/2”. So there are eight clicks per inch this time instead of 4, so in 2 inches there would be 16 clicks. Then for the remaining 1/2”, four more clicks would be required for a total of 20 clicks.

    For windage, I need 2” so that would be 16 clicks and all that’s left to do is two or three verification shots.

    When I sighted in my Aimpoint, I was off by about 1-1/2” low and 1-1/2” right. Since I wanted it to be ‘on’ at 25 yards, the distance from the blind to the feeder, each click would be change the POI by 1/16” – 25 yards is one-fourth of 100 yards, so the clicks would be one-fourth of a quarter of an inch or 1/16” per click. I then followed the same procedure as above.

    Before we move on to MOA type scopes, let’s do one more example where we’re not using a submultiple or multiple of 100 yards. Let’s say, for whatever reason, we want our scope zeroed at 70 yards. How do we do that? Really, it’s just like before except we have a bit more difficult numbers to deal with. Let’s use the POI at 70 yards as 1.5” high and 2” left.

    Like the previous examples, we have to determine how much each click changes the POI at the desired range, 70 yards in this example. We actually do the same thing, but it’s just a bit more ‘formal’. The value per click is obtained by dividing 70 by 100 and multiplying result by 1/4”:

    One click = 1/4” x 70 / 100 (I multiplied by 1/4” first – it’s a simpler expression.)
    One click = 1/4” x 0.7 = 0.175” per click

    Well, I warned the numbers weren’t so clean outside of submultiple/multiples of 100.

    Ok, so how many clicks are needed to change the elevation POI by 1.5”? This time dividing is probably the best method:

    1.5” / 0.175” per click = 8.57 clicks ??? How do we deal with a fraction of a click? Well we either have to go up or down to the closest click, in this case we’d be closer to 9 clicks.

    Same for the windage:

    2” / 0.175” per click = 11.43 clicks.

    This time the closest integer number is 11, so we would use 11 clicks.

    So that’s how the 1/4” at 100 yards type scopes work and the same thing applies to 1/2” at 100 yards except of course you use 1/2” to do the calculations instead of the 1/4”.

    In the next post, I'll discuss how the MOA works...
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    Part II MOA Scopes:

    First let’s be sure we know what ‘minute’ means in reference to scope specs. The MOA (Minute Of Angle) spec is an angular specification that is essentially independent of range. You might imagine a gun barrel perfectly horizontal and we fire a bullet at a target 100 yards away. Well, the bullet would hit really low. So to raise the POI, we would want to angle the muzzle of the barrel upward. We would use an angular measurement to describe how much we ‘tilted’ or angled the barrel. E.g. we could tilt the barrel upward by 1 degree and shoot again and see how that affects the POI. The problem is one degree is far too coarse of an adjustment to set the POI precisely. So we could change the tilt by tenths of a degree. But we would find that’s still too coarse to set the POI precisely. We need an even smaller change in angle to get the precision we need – enter the minute. A minute is one sixtieth of a degree and even that’s too coarse, but it is the basis of the MOA specification. So if we say a gun will shoot 1 MOA, it means that the gun can place hits within a cone that’s one-sixtieth of one degree. If a gun could shoot 1/2 MOA, it would be twice as accurate as the 1 MOA gun. Notice in none of this is anything mentioned about range. The spec is complete without a range dimension. Notice also how this contrasts with the 1/4” per click at 100 yards spec, where the 100 yards is an integral part of the spec.

    You may have heard that one MOA is 1” at 100 yards. Well, that’s close, but not quite. Changing the angle by one minute, would change the POI at 100 yards by 1.047”, not the 1” we hear so often, it’s really closer to 1-1/16” than 1”. But 1” may be close enough and if it is we can treat the sighting in of an MOA scope as if it was 1/4” at 100 yards and use the very same method to zero the scope that we did for a true 1/4” per click at 100 yards scope IF the clicks on the turret were 1/4 MOAs. That would still introduce a 4.7% error however.

    So, if we change the turret by one click on a MOA scope, how much does that change the POI? That depends on how the particular scope is set up and the range. For example, a Vortex Viper HS scope is a MOA type scope with 1/4 MOA per click. A Vortex Razor scope is also a MOA scope, but it has a 1/2 MOA per click. But the question stands, how much does one click change the POI? Let’s use the Razor in an example.

    We know one click equals 1/2 MOA. But how much that changes the POI, depends on how far away the target is. Let’s say the target is 100 yards away. At 100 yards one click will change the POI by 1.047”. How do we know that? Well, trigonometry is one way: POI = Range (inches) X Tan(1°/120). Or, we simply know, or accept that 1 MOA at 100 yards yields a value of 1.047”. So one-half MOA would change the POI by 0.523”. As you can see that’s a pretty coarse adjustment. A scope with 1/4 MOA per click would be close to the same as a 1/4” per click at 100 yards scope. In fact 1/4 MOA at 100 yards would give a change in POI of 0.262”

    Using the 1.047” at 100 yards we can calculate the clicks required to move the POI by the necessary amount to zero the scope.

    Other than treating a MOA scope like a 1/4” at 100 yards scope, there are two ways to determine the number of clicks required, one is to use a table – if you have one, the other way is to calculate the change per click. Here’s a formula to use for any range and any MOA.

    POI change per click = MOA change per click x 1.047 inches * range (yards) / 100 yards

    Where MOA change is the change per click, e.g. 1/4 MOA, 1/2 MOA and range is the distance to the target in yards.

    The 1.047 inches is the change in POI for 1 MOA change at 100 yards.

    So let’s plug in some numbers. Let’s use a range of 175 yards and a 1/2 MOA per click:

    POI change per click = 0.5 MOA x 1.047 * 175 yards /100
    POI change per click = 0.916”

    I actually used a completely different method - .5 MOA x 175yds * 3 ft/yd *12 in/ft * tan(1/2 MOA) and got exactly the same answer - just a corroborative calculation.

    Well that doesn’t sound very easy, especially in the field. But that’s what it takes – I know of no shortcuts other than calculating or table lookup. Bear in mind, a rangefinder won’t help at this stage; remember we already know the range - 175 yards.

    Ok, but let’s do a click calculation. Let’s use the very same measurements I used for the 50 yard bolt rifle in the 1/4” at 100 yards example:

    The range is 50 yards and the group was low by 2-1/2” and wide by 2”. So now, at 50 yards, with a 1/4 MOA scope, I have to calculate clicks required to bring the scope to zero. So first, as before, I have to calculate how much 1 click (1/4 MOA) moves the POI at 50 yards, so we use the handy formula from above.

    POI change per click = MOA change per click x 1.047 * range (yards) / 100 (yards)
    POI change per click = 1/4 * 1.047 * 50 yards / 100 yards
    POI change per click = 0.131”

    Notice the answer, 0.131”, is very close to the 1/8” (0.125”) per click we got with the previous bolt rifle example using the 1/4” per click at 100 yards type scope.

    So now, knowing the change in POI per click - at 50 yards, we can calculate the number of clicks needed to zero the scope by dividing the inches we need to move by the amount per click. Here's the calculation for the vertical:

    Number of clicks = 2-1/2” / 0.131” = 19.1 clicks.

    Again, notice how close 19.1 clicks is to 20 clicks we got in the previous bolt rifle example using the 1/4” per click at 100 yards type scope. The difference is that the click in the 1/4” (0.25”) per click is slightly smaller than 1/4 MOA (0.262”) for the same range.

    Next, we’ll look at the MIL system.
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    First let’s clear this up – MIL does not stand for MILitary or have anything to do about the military other than the military might use the MIL scope system. MIL means milli-radian. The MIL system is simply another way to divide an angle into very small divisions. Some manufacturers use ‘MRAD’ instead of MIL and you may see/hear the term MIL dot – they all mean the same thing in scope lingo.

    If we take the radius of a circle and fit that length right on top of the perimeter of a circle, we would have an arc with a length equal to the radius. The angle formed by that arc defines an angle one radian. Milli means one-thousandth of something – like millimeter, or milliamp. In scope lingo, a MIL is one-thousandth of a radian. A radian converts to 57.3° and a milliradian or MIL would be 0.0573°. Hence a MIL is a much larger angle than a MOA. An MOA is 0.0167°. So if one MOA was too coarse for precise POI adjustment, a MIL is way too coarse, hence the use of one-tenth MIL clicks which would give 0.00573°. In comparison, where the MIL system uses 0.1 milli-radian clicks, the MOA system uses 1/4 and 1/2 MOA clicks. So 0.1 milli-radians is an angle of 0.00573° and 1/4 MOA is an angle of 0.00417°. So the 1/4 MOA system gives a bit finer resolution than the MIL system and the 1/2 MOA (0.00833°) is a bit coarser than the 0.1 MIL click.

    We face pretty much the same issues with the MIL system as the MOA system; the same formula(s) we used for MOA works for the MIL system, we just have different numbers to work with. So let’s again start with how much one click changes the POI on a MIL or MRAD type scope.

    As with the MOA type scope, how much the POI changes per click depends entirely on the scope click design and the range. Since 100 yards is a pretty common range for hunting and we’ve used 100 yards in previous examples, let’s again use 100 yards as the range.

    Rather than talk about what manufacturers could do for click design, let’s use an actual example. Vortex offers their Razor HD with a 5 mil turret. That does not mean that each click is 5 mils, but one full turn of the turret changes the POI by 5 milli-radians. Each click changes the POI by 0.1 milli-radian. So now we know two of the three things we need – POI change per click and range. The third thing we’ll need is the POI change at 100 yards for one milli-radians.

    The change in POI at 100 yards for a 1 milli-radian change is:

    POI change = range (inches) x tan(angle)

    To use this formula we need the range in inches and we need to convert 0.1 milli-radians to degrees. To get the range in inches:

    100 yds x 3 ft/yd x 12 in/ft = 3600 inches

    To convert 0.1 milli-radian to degrees we start with 1 radian = 57.3°. We divide by 1000 to get milli-radians:

    57.3° / 1000 = 0.0573°

    Now plug in the numbers:

    POI change = range (inches) x tan (angle)

    POI change = 3600 inches x tan (0.00573°)
    POI change = 3.60” per milli-radian at 100 yards

    Now we can modify the MOA formula and use it for MIL calculations.

    Here’s the formula we used for the MOA system:
    POI change per click = MOA change per click x 1.047 * range (yards) / 100 (yards)

    And here it is modified to calculate POI change for the MIL system:
    POI change per click = milli-rads change per click x 3.60 * range (yards) / 100 (yards)

    I should comment here that the 3.60" is the amount 1 milli-radian changes the POI by at 100 yards.

    Let’s test our formula. We’ll use 100 yards for the range and 0.1 milli-rad per click:

    POI change per click = 0.1 (millirads per click) x 3.60” x 100 yds / 100 yds = 0.360”

    Now we’re set to go. Let’s do that same 50 yard calculation again. We had a POI of 2-1/2” low and 2” wide. So with a 0.1 mrad per click scope, how many clicks does it take to zero the scope? We simply take the amount one click changes the POI and divide that into the amount we’re off center by. However, we need to be careful, we are at 50 yards, not 100 yards so we have to scale our click values just like we did in the MOA example. Since 50 is one half of 100, then the change per click will be one half the 100 yard value:

    Change per click = 0.360” / 2 = 0.180” per click (at 50 yards)

    So now just divide:

    Number of clicks = 2-1/2” / 0.180” = 13.89 clicks.

    Well, that’s really close to 14, so we would use 14 clicks. We would do the same thing for windage and verify by shooting another group. If it’s on, we’re done; if not we make the appropriate adjustments which should be within one or two clicks. And then re-verify.

    Well, I’ve done a non-multiple/submultiple calculation for the first two methods so let’s do one for this one too. This time let’s use a range of 125 yards and say we’re off vertically by 3” and horizontally by 2”.

    As before, the first thing is to determine the POI change per click at the desired range. This is a simple scaling calculation. We always divide the range by 100 and then multiply that number by the POI change at 100 yards, e.g. in this case:

    POI change per click = 0.361” x 125 yds / 100 yds = 0.451” per click

    Let’s say the range was less than 100 yards, say 65 yards:

    POI change per click = 0.361” x 65 yds / 100 yds = 0.235” per click

    Now that we have the POI change per click at 125 yards, we can calculate the number of clicks. For the vertical part:

    Number of clicks = 3” / 0.451” per click = 6.6 clicks.

    Well, this one doesn’t work out so close. Since 6.6 is closer to 7 than 6, we would use 7 clicks.

    In closing, all three systems are kind of the same, but they are kind of different too. I’m pretty sure most would like the 1/4” at 100 yards method over the other two. It is a bit simpler to both understand and use.

    If there’s enough interest, I could do another thread about estimating ranges with a scope.
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    Good write up Tangle.

    One thing I would add, is that when adjusting elevation or windage, it is better to guess big than guess small.

    If you guess too big, it gives you a finite range within which the proper adjustment can be found. If you guess too small, you still don't have limits on the number of clicks you may need.

    Basically you are bracketing your target, in this case the target is a proper zero. And doing this helps reduce the number or rounds needed to achieve the goal.
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    I like the 1/4" per click at 100YDs, or 4 clicks will move POI 1", so at 400YDs range 1 Click would move POI 1" am I correct?

    Ok, at 800YDs 1 click moves POI 2", so bullet drop is, let say, 32" 16 clicks of elevation would put you on target providing there is no wind.

    This is new to me so I am trying to get it right.

    Thanks for your help!!!!
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    Quote Originally Posted by buckeye .45 View Post
    Good write up Tangle.

    One thing I would add, is that when adjusting elevation or windage, it is better to guess big than guess small.

    If you guess too big, it gives you a finite range within which the proper adjustment can be found. If you guess too small, you still don't have limits on the number of clicks you may need.

    Basically you are bracketing your target, in this case the target is a proper zero. And doing this helps reduce the number or rounds needed to achieve the goal.
    Bracketing is a common technique used in many applications and it works for zeroing scopes too. Bracketing is a form of trial and error.

    However, the methods I described is not trial and error, but a calculated adjustment that should put one very close to zero after the initial two or three shots. One then only needs to make two three confirming shots and make any small final adjustments needed.

    Quote Originally Posted by searcher 45 View Post
    I like the 1/4" per click at 100YDs, or 4 clicks will move POI 1", so at 400YDs range 1 Click would move POI 1" am I correct?
    You are correct!

    Quote Originally Posted by searcher 45 View Post
    ...Ok, at 800YDs 1 click moves POI 2", so bullet drop is, let say, 32" 16 clicks of elevation would put you on target providing there is no wind.

    This is new to me so I am trying to get it right.

    Thanks for your help!!!!
    You are right, but I want to be careful here. The methods I've described are for zeroing a scope at any range based on a scope's clicks and a reference range (or angle). The other thing one can do with a scope is adjust the zero, or hold, for the bullet trajectory at a specific range. The two things are very different.

    E.g. to zero a scope, one does not need to know anything about the bullet's trajectory because that's all taken into account by the shooting. But let's say we are zeroed at 100 yards and want to make a shot at 150 yards. Now we have to know the specific bullets trajectory in order to zero the scope for that range.

    In your example you know the bullet drop, so you can zero the scope, just like you described it, based on the bullet drop and the scopes POI change per click at 800 yards and it should zero pretty quickly.
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    Quote Originally Posted by luvmy40 View Post
    Ballistics makes my brain hurt!
    LOL! So true! And we haven't even talked about estimating ranges with a scope.

    The link you provided is quite interesting - actually the kind of stuff I do in one of my computer classes to illustrate graphical problem solving with a computer.

    However, while the formulas in the link are correct and exact, they are only for objects in a vacuum, i.e. wind resistance and ballistic coefficients are not taken into account so the actual trajectory of a bullet is significantly different than the equations in the link indicate, but they do illustrate the principles of objects in flight to a large degree.

    Thanks for the link - it's always good to see a corroborating presentation of things I teach. I much appreciate the link.
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    Tangle, as always, thank you for a clear and concise explanation of scopes! It is a great post!

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    Quote Originally Posted by Tangle View Post
    Bracketing is a common technique used in many applications and it works for zeroing scopes too. Bracketing is a form of trial and error.

    However, the methods I described is not trial and error, but a calculated adjustment that should put one very close to zero after the initial two or three shots. One then only needs to make two three confirming shots and make any small final adjustments needed.


    You are correct!


    You are right, but I want to be careful here. The methods I've described are for zeroing a scope at any range based on a scope's clicks and a reference range (or angle). The other thing one can do with a scope is adjust the zero, or hold, for the bullet trajectory at a specific range. The two things are very different.

    E.g. to zero a scope, one does not need to know anything about the bullet's trajectory because that's all taken into account by the shooting. But let's say we are zeroed at 100 yards and want to make a shot at 150 yards. Now we have to know the specific bullets trajectory in order to zero the scope for that range.

    In your example you know the bullet drop, so you can zero the scope, just like you described it, based on the bullet drop and the scopes POI change per click at 800 yards and it should zero pretty quickly.
    I agree that your method works, but it also requires repeatable adjustments, something that not all scope makers have mastered.

    If I had a scope with 1/2 MOA, or 1/2" adjustments, and through math decided that I had to move 9.49 clicks, I would still round up to 10, because I would rather be a little too far (giving me a finite range of adjustments within which the proper one exists). Than short.

    People in general tend to be extra conservative when making adjustments, like they are afraid to go too far. But, in this case, going too far is better than not going far enough, at least in my opinion.
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    Very cool posts.

    I used to work at a range that had shooting points every 25 yds to 100. A common question was where should my bullets hit at 25 yds to be on paper at 100. A lot of time was spent looking at the trajectory tables in the backs of gun catalogs and a lot of time and ammo was wasted with 3 shot groups at each yardage chasing zeros. I grew tired of that fast and spent some quality time with a program called Shoot! which you could get a free copy at Remington's website. Turns out that for all the flatter shooting cartridges from .223 to .416 if you adjusted your POI to be 3/4" low at 25 yds, you'd be somewhere in an 8" circle at 100 yds (from 4" high to 4" low). Given that there would be fine tuning necessary at 100 yds anyway, the real goal was just to get on paper at that distance. It works great and if you are a good shot you can be on paper at 100 yds in 2 shots - I always recommend at least one confirmation shot. However, for cartridges lobbing a chunk of lead, like a 45-70, you'll want to be 1.5" high.

    A guy came to the range on his last opportunity to sight in his son's rifle and when he was down to his last box of ammo he asked for help and it turns out his scope wasn't mounted correctly. I remounted his scope and had him hitting the bullseye at 100 yds in 4 shots - plenty of ammo left for his son to hunt with. I got invited to hunt his 200 acres that year.

    ETA: Ain't that the truth Buckeye, people would look at me like I was crazy when I told them to spin the turret 4x clicks when they were shooting at 25 yds.

  13. #12
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    Quote Originally Posted by buckeye .45 View Post
    I agree that your method works, but it also requires repeatable adjustments, something that not all scope makers have mastered.
    It's really not my method(s). It's just the method recommended by scope manufacturers and people in the know about scopes. I'm just explaining their methods.

    Quote Originally Posted by buckeye .45 View Post
    ...If I had a scope with 1/2 MOA, or 1/2" adjustments, and through math decided that I had to move 9.49 clicks, I would still round up to 10, because I would rather be a little too far (giving me a finite range of adjustments within which the proper one exists). Than short.
    Mathematically, and in reality, 9.49 is numerically closer to 9 than 10. The most accurate setting would be 9. You would be off by 0.49. If you set it to 10, you'd be off by 0.51.

    I don't see how either would be more forgiving, both 9 and 10 are off by essentially the same amount.
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    Actually, the Arty guys will give you a more procise answer. Grunts just shoot.
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    Here's a demonstrative video, provided by Vortex, illustrating the sighting method I described in my posts:



    You'll notice there is no guessing, no random adjustment, etc. He shoots three, sees where the group is and dials in that correction. He shoots three more for verification and finds the elevation a bit low, dials in that exact correction and fires three more and he is right on.

    This is the way about every serious scoped rifle instructor teaches it. I just bought a Nikon 223 scope and that's the method they describe although their instruction manual lacks the detail that I provided - we're still talking about the same method.
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