Question about ranging a target

[kaptain86]

Ok so I've miled a target using the height of the target on the left (sheet of paper 8.5"x11") and I was in the range of 92 yards. This is the SWFA SS 5-20x50 - Reticle subtensions here: http://www.opticstalk.com/uploads/298/5-20Reticle.jpg

I pulled up my photo in photoshop and measured using the measuring tool (I know the boxes are 1" and that works out to about 50 pixels per inch)

The actual 8" target measures to around 7.35" in photoshop - approximately 92% scale of the target.

Would a percentage scale also be accurate using a photoshop measuring tool? It appears as it is.

Here is the target I've been working on.


IMG_8188 by kaptain86, on Flickr

Can someone else mil this target and see how close I am?

 

[SIG700]

Re: Question about ranging a target

I just busted out the dial caliper and came up with 102.5 yards.

8 inch target (Measured .65 inches)
1 mil Measured .3 inches

8*27.78=222.24
(.65/.3 =2.166667 mils target height)

222.24/2.1666667= 102.5 yards.

 

[AtOne]

Re: Question about ranging a target

Using the target on the right and knowing that the paper is 8 1/2" wide it looks very close 2.4 mils across which would be right around 98.4 Yrds.

 

[kaptain86]

Re: Question about ranging a target

I need to track down a range finder and see what it tells me..thanks for your input guys.

 

[The_AKD]

Re: Question about ranging a target

Make sure your on the correct zoom as well.

 

[kaptain86]

Re: Question about ranging a target

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: The_AKD</div><div class="ubbcode-body">Make sure your on the correct zoom as well. </div></div>
The scope is a FFP so it doesn't matter what zoom it is on, but thanks for checking.

 

[louboyd]

Re: Question about ranging a target

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kaptain86</div><div class="ubbcode-body">I need to track down a range finder and see what it tells me..thanks for your input guys.</div></div>

This exercise shows the difficulty of using a stadia rangefinder even when you know the exact size of the target. It's not high level math but there's some error in visually estimating fractional mils. It's accuracy can't be better than your ability to estimate target size. Can you count on being able to estimate the size of targets which actually need shooting?

I'd agree. Track down a good range finder but use it all the time. The Mil-dot reticle can be used as a backup rangefinder but it's more useful for quick hold offs at moderate ranges.

 

[gman722]

Re: Question about ranging a target

Lou, I'm really glad to read your post. I've been practicing my mil ranging skills on known distance and known targets, and I find that it is difficult to do accurately. Sometimes I think that I just suck at this. There seems to be several factors that impact my read, haze, mirage, and very basic mil reticle. It seems that everyone else simply looks through the scope, gets a mil read, and easily calculates the exact range. I just needed to hear someone mention that it's really not that easy. More practice and attention to detail are in my future.

 

[Searcher]

Re: Question about ranging a target

Guessing is fun, but its better to KNOW. For that reason, I carry a Swarovski laser rangefinder. It has never let me down.

 

[kaptain86]

Re: Question about ranging a target

I'll have to look for a reasonably priced range finder, I don't need one that goes out past 800 yards I don't think...I don't have anything that I could shoot that far away anyways.

 

[BGE541]

Re: Question about ranging a target

For the sake of working on Mil ranging why dont you mil mulitul thing on that target stand (i.e. T post, plywood ect) and see what all mil estimates come out too, then see how good your estimation skills are. Never trust electronics alone!

 

[pinsandpitons]

Re: Question about ranging a target

Looking closely at the simple math involved, you'll notice that the larger the target measured the less important the inherent error of measuring mentioned above becomes. Trying to calculate range from the subtension of a door knob is way harder (and less accurate) then using the whole friggin' door. Use big things down range as much as you can.

 

[pinsandpitons]

Re: Question about ranging a target

Having said that..... I too think I suck everytime I calc a range as 548 when my LRF or range officer tells me it's 480. I'm there with ya brother!

 

[Sharpsman]

Re: Question about ranging a target

For me....I find it much easier to work in MOA. If I have a target that I know is 20" depth and it occupies 2 MOA real easy to figure 20/2x100=1000 yds.

 

[pinsandpitons]

Re: Question about ranging a target

Except that it would actually be at 955 yds. At that range 45 yds is the difference between a hit and a WTF did that go?. An MOA is not 1"/100 yds. I think it's 1.04... it adds up. (inches x 95.5)/moa = yds