Scopes with mildots and moa clicks?

[ScottMcc]

Reading scope specs on the Sightron website has me more confused than ever about mrads and moa. One mil dot is a mrad, or milli-radian, right? Do they equal 3.6 inches at 100y or 3.6 moa? In either event, why do scopes with mil dot reticles (mrad) have clicks measured in moa? Shouldn't the clicks be in mrad units?

 

[mao0720]

3.6in at 100yds is as near as makes no difference to 3.6 MOA.

 

[ScottMcc]

And a yard is about the same as a meter. If you just turn the knob til it goes where you want, then there is no difference. But the point of mildots and mrad marks is to accurately range targets and make the proper adjustments to connect on the first shot. It took a little longer to realize that Sightron has the LRMD-CM models, which are mildot reticles with .05 mrad clicks. That makes the units of measure consistent, although the measurements will vary with magnification.

 

[BobbyJ]

Reading scope specs on the Sightron website has me more confused than ever about mrads and moa. One mil dot is a mrad, or milli-radian, right? Do they equal 3.6 inches at 100y or 3.6 moa? In either event, why do scopes with mil dot reticles (mrad) have clicks measured in moa? Shouldn't the clicks be in mrad units?

Yes you are correct they should be the same. A good question.

"Do they equal 3.6 inches at 100y or 3.6 moa?"
1 Mdot=3.6" at 100 yards but 1 MOA is really not 1" its 1.047". So 3.6"/1.047 = 3.44 MOA not 3.6. Lots of little rounding errors can add up. 1 MOA at 95.5 yards is a true 1" but that would drive people nuts so we fudged and use 1 MOA = 1" at 100 yards.

MOA with MOA turret 1 click = approx .26" (100 yards)
Mrad with Mrad turret 1 click = .1 rad = 10mm (100m) or .36" (100 yards)

"Why do scopes with mil dot reticles (mrad) have clicks measured in moa?"

I've not see a good reason for this. It would have to come from the manufacturers. I have scopes that are Mdot/Mrad and MOA/MOA and Mildot/MOA.

I can guess at a few reasons for the mismatch reticle/turrets on some scopes.

1. Manufacturer bought the reticles from country using Metric system to be sold in US market. So they used MOA turrets because most Americans think in feet/yards/inches and 1 click = .25" at 100 yards is easier for the average Joe. They should have used MOA reticle but they got a better deal on Mdot reticles.

2. MOA turrets are a little finer 1/4" per click vs 1/3" per click of Mrad turrets. Maybe they sold better to US market.

Anyone know this for sure?

 

[Rob01]

Reading scope specs on the Sightron website has me more confused than ever about mrads and moa. One mil dot is a mrad, or milli-radian, right? Do they equal 3.6 inches at 100y or 3.6 moa? In either event, why do scopes with mil dot reticles (mrad) have clicks measured in moa? Shouldn't the clicks be in mrad units?

1 mil is 1 mil at 100 yards. 1 mil is 1 mil at 579 yards too. Do not get yourself confused brining in linear measurements which will mean nothing when actually using the scope. 1 mil is 3.44 MOA so if you are using a scope with MOA turrets and a mil reticle then you can either run your data in both MOA and mils depending on if you will hold or dial or do quick conversions if wanting to dial a correction instead of just reading it with the reticle and holding the correction. No need for linear anywhere.

As to why, well they used to be like that all over years ago but luckily companies got smart and started offering matching turrets and reticles, which is the best way to have it. Some companies still do mixed but I wouldn't buy one.

 

[Ray123]

Reading scope specs on the Sightron website has me more confused than ever about mrads and moa. One mil dot is a mrad, or milli-radian, right? Do they equal 3.6 inches at 100y or 3.6 moa? In either event, why do scopes with mil dot reticles (mrad) have clicks measured in moa? Shouldn't the clicks be in mrad units?

That was common years ago ...mils and moa mix...My old Mark 4 10× Leupold was mil dot reticle MOA turrents and it's finest ajustment was 1 MOA clicks, in elevation .5 Moa windage. It was USMC keep it simple stupid... I could go from 100 yard zerp to 1400 yds with one elevation turn, and back to 100 yd zero in the dark. No big deal learn to convert... mils to MOA. I use this scope with complete reliability....it on my 50BMG NOW ...a 2 mil wind was 7 MOA on the turrent...close enough guess, adjust after impact, and hold off on small adjustments. Like shoot opposite side of a 3" miss on a pop can, shoot again in 5 seconds before the wind changes and you hit the pop can, keep that hold until the wind changes in about 30 seconds. Or less.
Just use 3.5 MOA per Mil is close enough to shoot eggs and pop cans at 1000yds...just hold off on a close miss...by the time you dink around thinking about it, and calculating away, the wind changed..and your precise adjustment is no longer valid.
Shoot alot, practice with purpose, build confidence . Your mind is the main tool, feed back from your eyes, feel the conditions, expect to succeed on the shot no matter how long the shot or small the target...your optics will follow.

 

[BobbyJ]

1 mil is 1 mil at 100 yards. 1 mil is 1 mil at 579 yards too. Do not get yourself confused brining in linear measurements which will mean nothing when actually using the scope. 1 mil is 3.44 MOA so if you are using a scope with MOA turrets and a mil reticle then you can either run your data in both MOA and mils depending on if you will hold or dial or do quick conversions if wanting to dial a correction instead of just reading it with the reticle and holding the correction. No need for linear anywhere.

As to why, well they used to be like that all over years ago but luckily companies got smart and started offering matching turrets and reticles, which is the best way to have it. Some companies still do mixed but I wouldn't buy one.

Agree, it's always best to learn how to get a correction in mils by using your reticle without involving linear distance into the equation. I wish everyone used the metric system too.

I think people go linear sighting in and say oh im off by 1" thats 4 clicks. Or before range finders to get linear distance to target you could use the milldots on a known sized object. Today most people use range finders.

 

[Rob01]

No need to use the metric system either as that’s linear. Lol

I never use any linear to zero my scopes. I shoot, use the reticle as a ruler to tell me the correction and dial it until zeroed. .4 mils low and 1.8 mils left then correct .4 up and 1.8 mils right and point of impact is right at point of aim. Lol

 

[BobbyJ]

No need to use the metric system either as that’s linear. Lol

I never use any linear to zero my scopes. I shoot, use the reticle as a ruler to tell me the correction and dial it until zeroed. .4 mils low and 1.8 mils left then correct .4 up and 1.8 mils right and point of impact is right at point of aim. Lol

Not for that but you do need linear for distance to target. And that can be estimated using the scopes reticles but is not used much anymore.

I was explaining why people feel the need to stray off from angular values. As you pointed out they don't need to yet they do anyway.

 

[Rob01]

Not for that but you do need linear for distance to target. And that can be estimated using the scopes reticles but is not used much anymore. I was explaining why people feel the need to stray off from angular values. As you pointed out they don't need to yet they do anyway.

Yup always need linear to target but I was referring to people insane need to change mil or moa to a linear as in 1 mil is how many inches or cm at whatever range. Not needed we agree.

And when ranging you do need another linear in size of target to accurately get the range to target. If you don’t have it or estimating your range will be a estimate as well. Most can’t range well enough past 400-500 yards anyways but it is easier now with reticles breaking down the mil or moa into smaller units to make ranging with the reticle more accurate.

 

[BobbyJ]

I was referring to people insane need to change mil or moa to a linear as

LOL that line gave me a chuckle. Those insane folks are going to start calling you a "Linear Phobe"

People are just more familiar with inches and not angles. Mills and Mrad are not familiar terms to most people. Ask someone how many minutes of arc the moon subtends and you will get a blank stare. They are not insane just ignorant. Plus most scope manuals illustrate linear conversions so they help promote the insanity.

 

[slm9s]

For you experts, if you have a 2nd focal plane mildot variable scope w 1/4moa clicks, say a 6-24, shouldn't there be a power where the "mildot" will subtend an even number of MOAs? Say the mildot is subtending mils on 10x, I would think somewhere between 6 and 24x it would subtend 2, 3, or 4, etc MOA. This way even though its a "moa/mil" scope, you can use it as a moa/moa scope for spotting/corrections/etc.
Is there a mathematical way to figure this out? I don't own such a scope at the moment so I can't head out to the range with a yardstick.

 

[Rob01]

LOL that line gave me a chuckle. Those insane folks are going to start calling you a "Linear Phobe"

People are just more familiar with inches and not angles. Mills and Mrad are not familiar terms to most people. Ask someone how many minutes of arc the moon subtends and you will get a blank stare. They are not insane just ignorant. Plus most scope manuals illustrate linear conversions so they help promote the insanity.

If they call me that then they need to spend more time learning as anyone who knows wouldn't. LOL

Linear (Inches and CM) are like training wheels. People use them when learing but once they learn they take them off. Linear has a place but it's not in shooting with the scope.

 

[Rob01]

For you experts, if you have a 2nd focal plane mildot variable scope w 1/4moa clicks, say a 6-24, shouldn't there be a power where the "mildot" will subtend an even number of MOAs? Say the mildot is subtending mils on 10x, I would think somewhere between 6 and 24x it would subtend 2, 3, or 4, etc MOA. This way even though its a "moa/mil" scope, you can use it as a moa/moa scope for spotting/corrections/etc.
Is there a mathematical way to figure this out? I don't own such a scope at the moment so I can't head out to the range with a yardstick.

Yes there is and you nailed it with the last sentence. You have to go out and find it as even if a manufacturer says the mils subtend correctly on 15x, 15x on the power ring might not be exactly 15x so that is something that needs to be checked if you plan to use a SFP scope and use the reticle for holds or corrections.

 

[ScottMcc]

Good bump, BobbyJ! I ended up getting a Leup Mk4 8.5-25 in mrad, sitting happily on a R700 in 308.

 

[Rob01]

Didn’t even notice this was a necro post. Lol sorry for keeping it going.

 

[BobbyJ]

For you experts, if you have a 2nd focal plane mildot variable scope w 1/4moa clicks, say a 6-24, shouldn't there be a power where the "mildot" will subtend an even number of MOAs? Say the mildot is subtending mils on 10x, I would think somewhere between 6 and 24x it would subtend 2, 3, or 4, etc MOA. This way even though its a "moa/mil" scope, you can use it as a moa/moa scope for spotting/corrections/etc.
Is there a mathematical way to figure this out? I don't own such a scope at the moment so I can't head out to the range with a yardstick.

I like the question but it is making it more complicated than most people are willing to think about. I will try to go about it using a scope picture and some calculations. You are basically re calibrating the scope from Milldots to MOA markings.

Short answer is YES you could do that.

But... you need to take the actual scope out and have the distances nailed down as accurate as you can. Do not assume that the power on the scope is actually a true 12 or 24x either. It should be but I have tested many scopes where their 20x is really 14x.

The easiest way would be to make a target with clearly marked MOA lines from 1 to say 22 MOA. Then adjust the magnification to make 2 or 4 MOA fit into the space of the milldots. Most 6-24x scopes are calibrated for 12x for the mildots to be accurate. Testing at 6 or 24x should be a fraction of the calibration but not always true due many factors.

I will assume its variable 6-24x 2nd FP milldot scope with 12x being the calibrated power and with MOA turrents. So each miidot at 12x power = 3.44 MOA at 100 yards.

1 Mdot = 3.44 MOA at 100 yards or 3.6" (current scope at 12x)
Lets say you want:
1 Mdot = 4 MOA at 100 yards or 4.19"

Turn the power down from 12x until a object at 100 yards that is 4.19" tall fits between the milldots

Example:
at 12x power - 1 milldot = 3.6" or 3.44 MOA (1 MOA = 1.047" at 100 yards).
So you put a 3.6" orange circle at 100 yards and look through your milldot scope at 12x setting.
Wow it lines up perfectly. But then you relaize hey thats 3.44 MOA I want to to be an even MOA how can I do this? I want it to be 4 MOA per dot not 3.44 MOA.
Well how big would a 4 MOA object be at 100 yards?
it would be 4x1.047" or 4.19" tall. But thats too large to fit between my milldots how can I make that larger 4 MOA object fit between my fixed reticle dots?
Ans: Turn the power down until the 4 MOA object at 100 yards fits.

1 MOA = 1.047" at 100 yards.
2 MOA = 2.08"
3 MOA = 3.14"
4 MOA = 4.19"
=====================================================================
At what power will 1 mildot be 4 MOA in my 12x calibrated milldot scope?

X power = 4 MOA?
12x/4 = ?/3.44
12/4 x 3.44 = 10.32x power setting will give you 4 MOA per mill dot
=====================================================================
What if I want 1 MOA per milldot? Then you need to increase the power from 12x to make a 1.04" object fit the 3.6" (3.44 moa) per dots space
12/1 = ?/3.44
12x3.44 = 41.28x scope power. Sorry your scope can't do that.
========================================================================
The best you could do is 2 MOA per milldot.
12/2= ?/3.44 = 20.64X scope power will get you 2 MOA per milldot.
-------------------------------------------------------------------

I included a photo to illustrate it. Its just for and example the target is not really calibrated and not sure what distance that photo was taken.


Note: The power markings are too crude to really use for this. What you want to do is visually get the scope magnification and reticle calibrate the best you can then put a white marking on the scopes power ring to signify the new calibrated power setting for say 2 or 4 MOA per dot.

For your 100 yard target make marks every 4 MOA up to 22 MOA. In the 10.32x Photo the thick black line at the top of the target would be 22 MOA or 23.03" from the center. It would be more accurate to use the largest span of 22 MOA to align with the 5th milldot (where thick part of reticle begins)

Target markings: for 4 MOA per milldot 100 yards.
MDot 1 4 MOA - 4.19"
MDot 2 8 MOA - 8.38"
Mdot 3 12 MOA - 12.56"
Mdot 4 18 MOA - 18.85"
Mdot 5 22 MOA - 23.03"


Hope that was not too confusing.

 

[slm9s]

Nice. Thanks for writing that up.