Range Report Harry Potter and the Mil-Dot Master Mystery

[Red Ryder]

Sorry, I drank too much coffee this morning and when I do, I get a little out of control when writing subject titles.

So, I know some of you swear BY your mil-dot masters but I'm swearing AT mine today. I have ranged some targets using a GPS and a Zeiss LRF. By GPS, the target is 455 yards away. By LRF it is 450 yards away. The target height is 19.5" and using a Loopy TMR I'm milling them at ~1.20 - 1.25. When I use my handydandy mil-dot master I'm placing the 1.25 mil between the 19" and 20" and then reading the range which is showing at 440yards. In light of the more precise LRF and GPS measurements, this is obviously incorrect. When I approximately position the 19.5" over approximately 1.20 I get a more acceptable 450yards.

Now it's taken me like...1/2 hour to mil then re-mil then re-mil some more to get this close. In a hunting scenario, unless the animal is REALLY lazy, this is too long. And if I'd have gone with the first range I determined, I'd have probably missed.

I also tried to range using the formula target size x 27.77/mils and was substantially more successful so it's not like I'm a complete idiot.

The questions I have are:

Do you range a target say...3 times and then take an average?

How long does it usually take you to mil a target to a degree that you'll take a shot?

How accurately can you use a mil-dot master?

Your wise and experienced answers are always appreciated.

 

[bohem]

Re: Harry Potter and the Mil-Dot Master Mystery

You're within 10 yards of the correct range and you're not in the danger zone for anything but a 22 Hornet or smaller.

Mil-ing ranges isn't perfect and you're pretty darn close there. The difference in impact point is negligible, just kill the target and you're GTG.

 

[Lindy]

Re: Harry Potter and the Mil-Dot Master Mystery

Well, let's assume that your first take on the measurement was 1.25, leading to a range of 440 yards.

Your laser is probably closer to the true range than the GPS, so let's say that the true range is 450 yards.

That's a 10-yard error in ranging. It's not an interesting error, in that it won't lead you to miss a shot on a 19 inch target with most loads.

The difference is 0.3 MOA with my typical .308 load, and, at that range, that's about 1.4 inches.

Accuracy requirements for milling increase as range increases, as does the requirement to know the exact size of the target.

If you're using the method for hunting, you don't know the exact size of the target anyway, and the range at which the method is effective is limited.

The question is not how accurately you can calculate with a MDM, but how accurately you know the size of the target and how accurately you can measure it with the reticle.

If you can measure to 0.05 mil, i.e., half of a tenth of a mil, you'll be doing better than most and accurately enough for most real-world scenarios. Most people are happy with 0.1 mil, and it takes consistent practice to get better than that.

And if you are shooting at a range where you need that level of accuracy, use a calculator. The Mildot Master is for speed.

 

[Red Ryder]

Re: Harry Potter and the Mil-Dot Master Mystery

I know the 19.5" target size because I put them out there.

I also placed black tape at the edges of a piece of a 12" aluminum foil on the same target - hence the ability to accurately laze it.

Lindy I guess you're correct when you write that the real trick is knowing how to accurately use the reticle. I must admit I tend to allow too much "guesstimation" when milling.

 

[BobinNC]

Re: Harry Potter and the Mil-Dot Master Mystery

Red Ryder,

You over thinking it. My range dope is in 25 yd increments out to 1000 yds.. Whether I ranged a target @ 430, 440, or exactly @450, I always use the next highest value, which in this case would be 450 yd data. My 425 drop is 2.4 mils. My 450 yd drop is 2.6 mils.

On a 19.5" target, I would hold dead center, and fire away. Any difference between 2.4 MILS and 2.6 MILS is covered by the target, as Lindy points out.

If I was shooting @ a smaller target like a 4" or 6" plate, I again use the higher value, 2.6 MILS, and I use a 6 o'clock type hold on the lower half of the target, and fire away.

I train to hold on the lower 1/3 of the target, when I am using a MIL value at the next higher 25 YD increment.

Don't over think it.....

 

[gugubica]

Re: Harry Potter and the Mil-Dot Master Mystery

If you can mil a target and get a solution that is only 10 yds off at 450, you are doing better than most. That is only a 2% error.

 

[Red Ryder]

Re: Harry Potter and the Mil-Dot Master Mystery

Bob,

I'm rarely accused of overthinking anything. Just ask my girlfriend.

 

[The Mechanic]

Re: Harry Potter and the Mil-Dot Master Mystery

As the range increases you start getting into cumulative error also. like enviro conditions (elevation, baro, heat), wind, deviation of ammo, mil'ing errors, angle errors, not to mention the difference between your low left and high right shots. If by chance you have all or most align themselves in one direction it becomes a "how the hell did that happen?" or a "must have been bad ammo" etc.

 

[azimutha]

Re: Harry Potter and the Mil-Dot Master Mystery

Seems like you were generally right on and not a big error with the Mil-dot Master. Just happens that 1.25 mils is the lowest increment on it and since you don't have a precise tick for 19.5" inches, if you're trying to guess where 1.2 mils lines up with that on a logarithmic scale, it gets tricky.

Like these guys said, you are close enough as far as the range goes.

 

[BobinNC]

Re: Harry Potter and the Mil-Dot Master Mystery

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: azimutha</div><div class="ubbcode-body">Seems like you were generally right on and not a big error with the Mil-dot Master. Just happens that 1.25 mils is the lowest increment on it and since you don't have a precise tick for 19.5" inches, if you're trying to guess where 1.2 mils lines up with that on a logarithmic scale, it gets tricky.

Like these guys said, you are close enough as far as the range goes. </div></div>

Azimutha,

If you use the right side scale on your MILDOT Master, where it says Bullet Drop. Just ignore the words bullet drop, think target size, and use the MILS scale that goes down to 0.30 MILS, and read the target range on the left scale.

Then you do have a tickmark for exactly 19.5 inches and 1.25 MILS.......

For example if you read 0.8 MILS ranging (there is no 0.8 MILS on the left side) on a 14" TARGET, using the right side, just line it up 0.8 MILS and 14", and read 485 yds on the left scale.....

 

[Red Ryder]

Re: Harry Potter and the Mil-Dot Master Mystery

Well I guess that's another question I have - how much range underestimation or overestimation is too much? Bob uses increments of 25 yards. But when I was at Central Virginia Tactical this past May, it seemed like if I mis-ranged by 10 yards, it was enough to be a complete miss. Perhaps though, that was at really extended ranges past 600 yards?

I'm glad you mentioned using the bullet drop column Bob. I thought I'd heard of doing that and in fact, I was trying to sort it out today but was unable to do so.

 

[BobinNC]

Re: Harry Potter and the Mil-Dot Master Mystery

RedRyder,

Yes, the longer the range, the greater an error in ranging results in a miss.

For example, the difference in drop in MILS between 975 and 1000 yds. for my 308 is 0.6 MILS. That's 21.6".....

 

[GCMxVeGeTa]

Re: Harry Potter and the Mil-Dot Master Mystery

For 450 yards you should be close enough with your estimate to take a deer sized animal. You could even use the formula (#yards/#mils = 0.### <- - -range) and use the bottom of leg to top of back as the yard measurement and still be close enough to take the shot. Plus this formula is faster than (inches*27.77/mils) because you don't need a calculator as much or at all. But either way should work out to 600 yards or so until you can get a LRF.

 

[LoneWolfUSMC]

Re: Harry Potter and the Mil-Dot Master Mystery

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RedRyder</div><div class="ubbcode-body">I must admit I tend to allow too much "guesstimation" when milling. </div></div>

There should not be any "guesstimation" when milling. You are MEASURING the target. It should be correct to the tenth of a mil. If you can get to .05 mils, that's even better.

Being exact with the measuring limits the other errors that sneak into the formula (mirage, target size, perspective, etc.)

 

[Red Ryder]

Re: Harry Potter and the Mil-Dot Master Mystery

Yes you're 100% correct LoneWolf, since I'm in the hobby (and you're a professional at it)of "precision" shooting there shouldn't be guesstimation. But right now, my eyes/brain isn't as skilled as they should be at distinguishing those tiny 1/10 increments between the hash marks. I feel pretty uncomfortable with throwing lead downrange based on a guesstimation. That's why, when possible, I use a LRF to backup my milling. And if I can't get a reasonably accurate range, I don't take the shot. But I do believe that to be a well-rounded shooter, I need to know how to mil.

 

[Woodlanddude]

Re: Harry Potter and the Mil-Dot Master Mystery

Also, don't overlook the effects of slight angles between you and a thin plate. If you are not perfectly tangent to the face of the plate (uphill/downhill, left/right) you are not getting the full measurement. If you are level with a target, but off left to right mil the height. If you are high or low, but square, mil the width. If unsure, but close both ways, mil both and check your range. It is not perfect. In this case you were closer than the LRF said, so I don't think it was your problem, as this error puts you at a longer range than actual. If you need a 100% exact solution you can use the mildot formula. If you have an Angle cosine indicator on your rifle or measure it with your MDM and a weighted string(what the hole on the MDM is for), you can also multiply the target ht. x the cosine and use that ht. for your target size and range normally. 10 yds is not to shabby IMHO! ALSO, Light target colors "glow" in certain light conditions. If you are shooting flourescent or white, you may try shading the edge of one side with a tick mark and use the same point on the other edge for your reading. The glow CAN give you a little closer range than actual, as you are milling more than the actual target size!!! I have seen targets with consistant high shots when they were glowing some. I learned this the hard way! You sound like you know how to mil, you just need practice!! The new shooter ready demo looks very promising as cheap practice for those of us who even have a couple months down time from shooting now and then.

 

[Red Ryder]

Re: Harry Potter and the Mil-Dot Master Mystery

Woodland, I was wondering about that angle factor. I'm downhill and to the right of the target. While I can't give you an exact grade, the uphill angle is not that much. The targets are not facing me headon. Commonsense told me that if the targets were not facing me headon, I was probably getting some builtin inaccuracy. BTW, the targets are those thin flat flexible plastic markers that you see alongside bike trails or roads. They're about 5" wide by about 33" high.

 

[azimutha]

Re: Harry Potter and the Mil-Dot Master Mystery

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BobinNC</div><div class="ubbcode-body">
Azimutha,

If you use the right side scale on your MILDOT Master, where it says Bullet Drop. Just ignore the words bullet drop, think target size, and use the MILS scale that goes down to 0.30 MILS, and read the target range on the left scale.

Then you do have a tickmark for exactly 19.5 inches and 1.25 MILS...</div></div>

Hadn't thought of that. Thanks for the tip.

 

[azimutha]

Re: Harry Potter and the Mil-Dot Master Mystery

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: woodlanddude</div><div class="ubbcode-body">If you are level with a target, but off left to right mil the width. If you are high or low, but square, mil the height.</div></div>

Shouldn't that be the other way around?

 

[Woodlanddude]

Re: Harry Potter and the Mil-Dot Master Mystery

azimithu is correct, I F#$%*@ up and typed it bass ackwards. level with target.. mil height
high/low... mil width

 

[marduk185]

Re: Harry Potter and the Mil-Dot Master Mystery

dont forget to compensate for coriolis.

 

[Red Ryder]

Re: Harry Potter and the Mil-Dot Master Mystery

don't go there.

 

[azimutha]

Re: Harry Potter and the Mil-Dot Master Mystery

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: marduk185</div><div class="ubbcode-body">dont forget to compensate for coriolis.</div></div>

Or for cornholius (sometimes a problem when shooting prone in urban environments)

 

[marduk185]

Re: Harry Potter and the Mil-Dot Master Mystery

spin drift

 

[marduk185]

Re: Harry Potter and the Mil-Dot Master Mystery

planetary alignment