MOA/ranging math... but really programming question

[T.Lex]

My programming (historically) has been better than my math. So, when I got a new scope with mildot ranging, I sat down and started to work up a spreadsheet to help me with ranging. The scope is 4-16x50 and the reticle is called a "wire mildot" which I think is proprietary, or at least non-standard.

The good news is that it comes with some diagrams that explains the MOAs at different magnifications for the BDC.

At 16x, the dots below center are at (MOA):
1.4
4.3
7.2
10.4
15

At 4x, the BDC drops are (MOA):
5.6
17.2
28.8
41.6
60

I've figured out (I think) the progression for the first dot across the different levels of magnification [sqrt(2)*(16/zoom)] but I can't sort out the math for the progression of dots along the BDC. The scope came with handy reference stickers for the inside of the eye piece, but I want to have it programmed so I enter the zoom, the dots, and the estimated height, and get a range.

Anyone have an easy answer for that?

 

[ScouT6a]

BDC is much easier these days, than a Mil Dot relation formula.
I use the Nikon Spot On app on my phone. Enter the caliber of ammo, bullet weight, fps and B.C. info and it does all the calculations for you. Even at each magnification setting.
Or get a custom made turret for your scope that is made with all the same info.
Years ago, I ran a Springfield Armory scope on my sniper rifle that had an internal rangefinder and level. It was three times as fast as the Mil Dots.

 

[ChristianPatriot]

Get a mil-dot scope

 

[T.Lex]

Yeah, there are stickers for the BDC itself, so I'm not as worried about that. And, honestly, my shots with this scope will likely be less than 300 yds. I'm really trying to get the calculations for ranging.

At x zoom, y dots is how many yards to target....

 

[T.Lex]

Get a mil-dot scope

I thought I did...

 

[ChristianPatriot]

You don't think you'd be able to make a hit with either the 4x or 16x? I mean do you NEED to know what all the other magnifications equate to in order to make a hit?

 

[T.Lex]

You don't think you'd be able to make a hit with either the 4x or 16x? I mean do you NEED to know what all the other magnifications equate to in order to make a hit?

Well... it isn't really about that at this point.

This spreadsheet is mocking me.

Its saying that it knows the answer, but it won't tell me.

It just sits there and laughs while I try different ways to figure this out.

And now, its gotten a pad of paper involved in ridiculing me. They just stay there, impassively holding in the chuckles while I think back to the hardships that were trigonometry and calculus.

When I stop, I just know they'll giggle behind my back every time I walk by.

I can't let that happen. I can't let them know they've bested me.

Anyone who's tried programming will know what I mean. I think.

 

[Clay Pigeon]

My programming (historically) has been better than my math. So, when I got a new scope with mildot ranging, I sat down and started to work up a spreadsheet to help me with ranging. The scope is 4-16x50 and the reticle is called a "wire mildot" which I think is proprietary, or at least non-standard.

The good news is that it comes with some diagrams that explains the MOAs at different magnifications for the BDC.

At 16x, the dots below center are at (MOA):
1.4
4.3
7.2
10.4
15

At 4x, the BDC drops are (MOA):
5.6
17.2
28.8
41.6
60

I've figured out (I think) the progression for the first dot across the different levels of magnification [sqrt(2)*(16/zoom)] but I can't sort out the math for the progression of dots along the BDC. The scope came with handy reference stickers for the inside of the eye piece, but I want to have it programmed so I enter the zoom, the dots, and the estimated height, and get a range.

Anyone have an easy answer for that?

Good luck with the proprietary mil dot, I use the old Marine mil dot on my Leupolds and that's about it.
What does the little bookie that came with the scope say?

 

[T.Lex]

Good luck with the proprietary mil dot, I use the old Marine mil dot on my Leupolds and that's about it.
What does the little bookie that came with the scope say?

That if I'd gotten the more expensive model, the ranging would be on the magnification ring.

It has the MOA measurements at 4x, 8x, and 16x. That still leaves memorization and math to my old school brain. Which is less than ideal on both counts.

I'd like to have a spreadsheet that I can have on my phone where I enter the zoom, estimated height, and how many dots, and it'll give me a range.

ETA:
I am actually pretty decent with my 30/30 reticles. This'll teach me not to get fancy. Or get much fancier. One or the other.

 

[Clay Pigeon]

BDC is much easier these days, than a Mil Dot relation formula.
I use the Nikon Spot On app on my phone. Enter the caliber of ammo, bullet weight, fps and B.C. info and it does all the calculations for you. Even at each magnification setting.
Or get a custom made turret for your scope that is made with all the same info.
Years ago, I ran a Springfield Armory scope on my sniper rifle that had an internal rangefinder and level. It was three times as fast as the Mil Dots.

Mil dot can be used just as fast if not faster for quick range finding,
250 meters =side of head to side of head.
500 meters = shoulder to shoulder .. with a 10 power you can range out to a 1,000 easy peasy.
Have you ever wondered why Springfield stop selling those Chinese scopes?

 

[T.Lex]

BTW, I have Strelok+ and the closest reticle I can find (REALLY wish he'd do a visual guide to all of them) is the XTR Ballistic Mildot by Burris. It pretty closely matches the info that came with the scope. But, to really get the most out of Strelok, I need the range.

 

[Clay Pigeon]

That if I'd gotten the more expensive model, the ranging would be on the magnification ring.

It has the MOA measurements at 4x, 8x, and 16x. That still leaves memorization and math to my old school brain. Which is less than ideal on both counts.

I'd like to have a spreadsheet that I can have on my phone where I enter the zoom, estimated height, and how many dots, and it'll give me a range.

ETA:
I am actually pretty decent with my 30/30 reticles. This'll teach me not to get fancy. Or get much fancier. One or the other.

Lol.. I do understand.

 

[Ericpwp]

Why not make it easier and only range from one zoom level? This is a second focal plane scope, right? Then bdc from desired zoom.

 

[Ericpwp]

It is probably setup for a mildot = 1 milrad @10x. But it is usually impossible to tell when you are at 10x.

 

[jinks]

You could purchase a phone app like Strelok Pro for $13. Additional scopes are added frequently and the updates are free.

 

[T.Lex]

Yeah, I can hardcode ranges for the difference zoom levels or just make pictures. Was just hoping there was a math way to do it.

The more I play around with it, the stranger it gets. The increments don't even appear linear or exponential. So, probably proprietary. Yay.

 

[Ericpwp]

The model would help.

 

[T.Lex]

It was a Christmas present.
Field & Stream 4-16x50 Rifle Scope| DICK'S Sporting Goods

From my kids.

Whom I love very much and am very appreciative of this gift that they put a great deal of thought into.

 

[Ericpwp]

Yeah, you got me. I'm no gear snob though. It sounds like a BDC reticle being that they're not equal graduations.

 

[jrh84]

I'll be back on my laptop later tonight and get you an answer. I've done stuff like this tinkering around in my spare time, and to help give the neighbor kid some real world examples instead of textbook math problems.