Perfect Union banner
1 - 20 of 38 Posts

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #1 ·
Probably a simple question, but one that has never occurred to me before, because the last rifle I had this scope on was for varmints, and they were close enough I didn't have to change the power past 8x which it's calibrated to.

Anyway, question is this. Since Mil-Dot scopes are basically designed to work from ratios between target size and mils read, (mine's calibrated to 8x) can't you zoom to 16x for smaller targets, calculate range like normal and then double the range you come up with since you're at twice the power it's calibrated to? And same would go for 24x and triple the answer, correct?

Or is my mind telling me some messed up stuff right now?
 

·
i like the details
Joined
·
254 Posts
Probably a simple question, but one that has never occurred to me before, because the last rifle I had this scope on was for varmints, and they were close enough I didn't have to change the power past 8x which it's calibrated to.

Anyway, question is this. Since Mil-Dot scopes are basically designed to work from ratios between target size and mils read, (mine's calibrated to 8x) can't you zoom to 16x for smaller targets, calculate range like normal and then double the range you come up with since you're at twice the power it's calibrated to? And same would go for 24x and triple the answer, correct?

Or is my mind telling me some messed up stuff right now?
i dont think it works like that, there would have to be some pretty complex seredipity. Unless of course your retical is in a different focal plane.
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #3 ·
Has to do with stadia is the way I'm thinking. I'm a land surveyor also. No matter what power the transit is you're looking at, the wires are set the same distance on all of them, so you can range a rod to nearest foot.

Maybe I'll just have to experiment and see.
 

·
i like the details
Joined
·
254 Posts
I dont know anything about surveying, but i do remember somthing in a class i took about camera tricks and that a telephoto lens tens to compress angles as opposed to just being closer. I think they called it the Hitchcock effect, you probably seen it in movies where the camera is moved back while zooming in on a person. It then appears that more field of view is available while the person doesnt appear to change.

Anyway, i think the angles dont scale correctly, but let us know if you find something different.

Has to do with stadia is the way I'm thinking. I'm a land surveyor also. No matter what power the transit is you're looking at, the wires are set the same distance on all of them, so you can range a rod to nearest foot.

Maybe I'll just have to experiment and see.
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #6 ·
Great link. But no, it didn't really answer what I wanted to know.

I did get out to test my theory, but unfortunately, a break to my wrist some time back, and the metal within, don't allow me to hold the standard stock on my .30-06 comfortably, so I was pretty inconsistent. Going to upgrade it to a target stock and try again.

First attempt says it just might work, though I was wrong on the doubling. It needs to be cut in half when you double the power. More tests needed though before I swear to it.
 

·
Registered
Joined
·
10 Posts
The simple answer to your 8x to 16x is yes.

If you have a First Focal Plane reticle then the mil dot stays constant through the zoom.
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #8 ·
Thanks! I still need to test it out though. The target scope I bought for varminting years back for my .243 is Army mil-dot 8-24x. I've used the actual dots @ 8x to range most of the targets because they were usually small. But all of a sudden, I had the clever idea of using the multi power and adjust accordingly, instead of trying to range a Prairie Dog 350 yds away with the dots.
 

·
Registered
Joined
·
45 Posts
Old thread, but even if your scope is second focal plane you can still mil your target. If your scope is second focal plane, set up a target ( cardboard works best ) at 100yrds and draw a line down the center. Take a ruler or tape measure and make a horizontal line ever 3.6 inches threw the vertical line, with a total of 4 horizontal lines. Line your cross hairs up with the bottom line on the target and adjust your magnification until the mil dots line up with the marks you made on the target. Once you do that and the mils line up, take some white out and mark it on your scope.. Or make a mental note.
That will allow you to mil your target with a 2nd focal plane scope.

If the target is 68in tall ( the average hight of a man ) multiply 68x 27.77 or 27.8, then divide that number by how many mils the target takes up.. That will give you your range.
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #10 ·
27.77 is a pretty specific number. Mind if I ask where you get it from?

Forgot I even created this thread, but I have come up with the answer, and it was much simpler then that IMO. I went out to Ft. Bliss Rod & Gun Club where they actually have a 1,000 yd range. Set up a 36 inch piece of cardboard painted white leaning against their steel. When I looked at it with scope at 8X it did indeed cover 1 full Mil. Zoomed to 16X, it covered 2 full mils, and covered 3 mils at 24X.

So, if a 36 in target covers 1 mil at 8X and 1000 yds, a 6 ft man will cover 2 mils at the same range and power, or 4 mils at 16X, etc. A little more work involved if you want to use any of the in between powers of the scope, but if you increment the power, 8X to 16X, to 24X, it's simple as dividing what you get by 2 or 3 respectively. But still requires you to know the rough size of the target. ;)

Would like to know where you get that number from though. I'm a curious sort of person. LOL

Thanks!
 

·
Registered
Joined
·
45 Posts
That's just one of the mil formulas. You can also do it like this.. If a target is 1 meter tall, multiply that by 1000, then divide by the mils.
The 27.7 is for inches to yards, it's not as accurate as the 1000 formula, but its easier for me and it's almost as accurate.. Like within 2 yards accurate

So 1 meter times 1000= 1000 say the target is 4 mils high and you divide that you get 250m
If something is 70in tall, multiply 70x27.7=1939 then divided by say 3 mils=646 yards

There's a few different ways to do it, but the inches to yards is what's easiest for me.
 

·
Registered
Joined
·
45 Posts
Here is something that breaks it down a little bit better than I can explain it

Using mils to judge distance is very easy and mils are very flexible for this purpose. Now the mil formula works by dividing the size of the target in millimeters by the apparent size of the target in mils. This is why the 1000 formula works so well. Size of the target in meters times 1000 divided by the apparent size in mils. 1000 is the number of millimeters in a meter. Thus if you have a one meter target and multiply it by 1000 you have converted the 1 meter into 1000 millimeters. Now the neat thing about the mil formula is that it assumes that everything is meters and dutifully gives answers in all manner of sizes. Thus if you were to say the size in yards then the answer would be in yards, if in feet the answer in feet, inches answer inches. Thus a 2 yard tall target milled at 4 mils would become 2 times 1000 divided by 4 which equals 500 yards distance. A 6 foot target milled at 4 mils becomes 6 times 1000 divided by 4 equals 1500 feet which also seems to be 500 yards. I could continue in inches but my head is already hurting. This is great for those easy to do times 1000 deals but car tires, tank fenders and a few others may be a bit more problematic. 45 inches does not do well times 1000 converted into meters or yards. You can convert 45 inches into meters but why not simply multiply 45 times 25.4 (number of millimeters in an inch) and divide that by the apparent size of the target in mils. So now 45 times 25.4 divided by 4 mils equals 285.75 meters. For those of you that wish to work in inches you can use 27.7 instead of 25.4. This tricks the formula into converting the range into yards for you. While this is not perfect, it works. Example is the two yard tall target, 72 inches times 27.7 divided by 4 equals 498.6 meters versus 500 yards using the 1000 formula. I can live with the error. When using the mils you must be able to break the mils into 10ths. This can be done based on the dots themselves. The dots are .22 mil but half is .11 mil. Using this information you then rest the target on the top or bottom of a mil and then measure up. Say, top of one mil to bottom of second mil and the reading is 1.8 mils. Another example would be bottom of one mil and top of second mil and you have 2.2 mils. Combinations of the above will give you anywhere in the tenth scale.
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #13 ·
36 Inches is 1 U.S. yd exactly. You sure you're not trying to go from meters to yds/yds to meters or something? 1 foot is equal to .3048 meters. 1 meter is equal to 3.2808 ft. for shooting purposes anyway.

Unless you're dealing with astronautical numbers, like state plane coordinates or something. Then the number to convert is literally like 17 digits long, or you'll be hundreds of meters off. Being a land surveyor, I use those conversions a lot. :)
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #14 ·
OK, seeing your second post, I see what you're doing. There is a much easier way though...it's called a Mil-Dot master. A slide rule type of tool that makes all that much much easier.
 

·
Registered
Joined
·
45 Posts
What I put is 100% accurate. This is how I was taught and how it's still being taught. Get your scope out and put a target up, measure it, pull your scope out and mil it, then if you have a rangefinder, hit it with your rangefinder and it will be within 1-2 yards, or meters depending on what formula you use..
I was a Designated Marksman in the Army and this is how I was taught.
I'm going to a sniper course in May, so I'm sure I'll be able to elaborate more then. Steve Reichert, James Gilliand, and Rob Furlong are teaching the course... btw
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #16 ·
I understand that now, as I posted above. The numbers I gave will get you within cm, not a meter or two, which for my trade is needed.

For shooting purposes though, like I said, I see what you're saying. Didn't mean to sound like I was saying you're wrong.

Thanks!
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #18 ·
Meant to tell you good luck at counter sniper school too, but it slipped my mind. Is the Army still using fixed 10X scopes on their M24's? Been out since 1987, so things might have changed some, including the weapon of choice. LOL My buddy at Benning was a sniper and had an Unertl 10X scope on his. Pretty sweet scopes if you ask me.

Anyway, good luck!
 

·
Registered
Joined
·
45 Posts
Yeah for the most part, the m24's are still using fixed 10x, but M110's are being used a lot with SASR's and the new bolt gun...forgot the name. The m110's have an adjustable scope, same for the SASR ( M107 ).. I'm out now too, but the course I'm going to is ran by x military that work the civilian side of it now.
Reichert has the longest confirmed kill on OEF, Gilliand has the longest confirmed with a 7.62, and Furlong had the longest confirmed until not long ago when a british guy claimed it.
It should be a good class
 

·
The Snake Guy
Joined
·
131 Posts
Discussion Starter · #20 ·
Craig Harrison is the British guy if I remember correctly, with a mile and a half confirmed kill using a L115A3. An Army friend sent me a link not long ago about it. Beat the record by a mere 150 ft or so.
 
1 - 20 of 38 Posts
Top