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@epaultmbt mentioned small targets are hard to mill. Thats true, but I guess it would make sense to explain what I meant about "not be able to accurately mil range an IPSC when mirage is up at ELR distances.." Because this isn't a small target. What mirage does is make the targets look larger than they are, so "mil ranging" is very problematic for precision shooting at very long ranges.
Below is what I do, I am not saying is it the correct way, just what I do and why the math fails with horribly short on reasonable sized targets with mirage and longer ranges.
Close range:
Yards as Target size: Normally for speed I'd use yards for size of target were 1 is 36" I'd only brake it down by quarters.. so I am working with 9" =.25; 18"=.5, 24"=.75; etc.. x1k /visual. This works great at 800 and in.. super fast without a calculator, (usually) and close enough for the most part.
For further ranges:
Inches as Target size X 27.77 (or divide by 36x1k) /by visual - you need a calculator/phone/pen or whatever-- at least I do. So for easy math lets use a 24x24 plate note the IPSC Silhouette @ 30"x 18" because can't make out the head so you have a fussy 24" T target or a smaller 18"
Below is an image from a real f up we had. I will use this because we all are accomplished enough mil ranging, but this was such a cluster, it sticks well in my memory and we all made a lot of wrong decisions. Usually, if we can see the impact, you can quickly figure out a bad decision.
Setting the stage,
We we getting most of the lazed returns from the ridge just prior to the target, but did not know it. The target appeared to be sitting on this ridge at 1650 yards. We were also getting a few returns at 2195-ish. To confirm, we dropped onto the spotting scope and the target appeared to be .425 mil+
Using .425mil would yield 1568 we rounded down for mirage (a huge guess) to .4mil we got a read about 1,660. So we had a high but almost identical read to the majority of the lazed returns, saying 1650 .. Arn't we cool..
Round 1 - no Visual - same for all shooters
Several rounds in we stopped all no visuals
We ranged a rock hill to our left at 1650 and all of our dope was money..
Back to the target -- all no visuals -- WTF we al thought.
Anybody guess why we had no visuals? We were too F'd wrapped up in our mil reading ability..
Here is the hint - the mirage made the visual over 1.25mil larger appearing than it should have been. Even though we all were aware of the larger appearing images, the numerous erroneous lazed returns from the ridge at 1650 and confirmed visual and HORRIBLE mil read.. had us waste tons of time, ammo..
Issues:
1: The position of the Target no real back stop at it is on the top of a ridge (red arrow)
2: The green lines are dead space created by the rolling hills. From prone you do not see that 300-400 yards are hidden, just before the target.
(this we did NOT realize while shooting and ranging- the rounds were dropping into this dead space.)
3: Lots of vegetation from the prone position leaves little visual on the target
4: The above gave lots of weird returns from the Vectronix way more at 1650 than 2195 - but we should have known it had to be the target 500y further.
5. A lot of Mirage, increases the appearance size of some objects even though we tried not to count the bounce of the image.
6. never set your target up with dead space leading all the way up to the bottom edge and no backstop.
Long story short The range finder was working correctly, the - mill ranging LR and ELR is/was problematic, just a waste if you can't see the misses.
