Understanding Milliradians

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TattooedGun
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Understanding Milliradians

#1 Post by TattooedGun »

This topic always baffled me, so I put some time in to understanding it and wrote my findings in what I hope is easy to digest information which may help others better understand the angular measurement.

http://blog.stegough.com/understanding- ... il-milrad/

Kind Regards,
TG
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Sim G
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Re: Understanding Milliradians

#2 Post by Sim G »

I think you explained it rather well....
In 1978 I was told by my grand dad that the secret to rifle accuracy is, a quality bullet, fired down a quality barrel..... How has that changed?

Guns dont kill people. Dads with pretty Daughters do...!
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Re: Understanding Milliradians

#3 Post by Polchraine »

Can I correct one thing for consistency.

Your diagram at the top shows a radian as 57.29578 degrees which is correct (to 5dp) however at the end you state it as 57.29564 degrees.


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Re: Understanding Milliradians

#4 Post by TattooedGun »

Polchraine wrote:Can I correct one thing for consistency.

Your diagram at the top shows a radian as 57.29578 degrees which is correct (to 5dp) however at the end you state it as 57.29564 degrees.
Thanks,

it depends really how many digits of pie you work to in the original instance. The more digits to pi you can calculate to, the more accurate the calculation of Radian.

2x Pi to 6 dp yeilds the "correct answer".

360/6.283185 = 57.29578

2x Pi to 5 dp yeilds 57.29582

I think I must have done it from 4 dp to be so far out.

Bottom line is it doesn't need to be sooo specific as 57.3 is plenty accurate enough for explaining it, but definitely worth noting for the consistency, so thanks, and it's been amended :)
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Re: Understanding Milliradians

#5 Post by meles meles »

TattooedGun wrote:
it depends really how many digits of pie you work to in the original instance.

Little Jack Horner might have his digits in a pie, but here we ought to be referencing pi, the Greek letter and mathematical ratio, ooman...
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Re: Understanding Milliradians

#6 Post by TattooedGun »

meles meles wrote:
TattooedGun wrote:
it depends really how many digits of pie you work to in the original instance.

Little Jack Horner might have his digits in a pie, but here we ought to be referencing pi, the Greek letter and mathematical ratio, ooman...
mmm... pie....

Must be hungry...
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Re: Understanding Milliradians

#7 Post by Polchraine »

TattooedGun wrote:
Polchraine wrote:Can I correct one thing for consistency.

Your diagram at the top shows a radian as 57.29578 degrees which is correct (to 5dp) however at the end you state it as 57.29564 degrees.
Thanks,

it depends really how many digits of pie you work to in the original instance. The more digits to pi you can calculate to, the more accurate the calculation of Radian.

2x Pi to 6 dp yeilds the "correct answer".

360/6.283185 = 57.29578

2x Pi to 5 dp yeilds 57.29582

I think I must have done it from 4 dp to be so far out.

Bottom line is it doesn't need to be sooo specific as 57.3 is plenty accurate enough for explaining it, but definitely worth noting for the consistency, so thanks, and it's been amended :)
Totally agree ... that is why I said "consistency"

I have a fairly detailed maths background - passed my A-level maths at 15. It irritates me when someone works to say 10 dp (or significant figures) when just one will do or they work to 1 or 2 when a lot several more are needed. You have, in my opinion, got it about right. Do the calculations at 5 or 6 dp and then give the final answer to just 1 - 57.3 degrees.


And what about adding Gradians to the mix? 1 gradian = pi/200 radian
Last edited by Polchraine on Mon Feb 08, 2016 6:04 pm, edited 1 time in total.


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Why did kamikaze pilots wear helmets?

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Re: Understanding Milliradians

#8 Post by TattooedGun »

Polchraine wrote:
TattooedGun wrote:
Polchraine wrote:Can I correct one thing for consistency.

Your diagram at the top shows a radian as 57.29578 degrees which is correct (to 5dp) however at the end you state it as 57.29564 degrees.
Thanks,

it depends really how many digits of pie you work to in the original instance. The more digits to pi you can calculate to, the more accurate the calculation of Radian.

2x Pi to 6 dp yeilds the "correct answer".

360/6.283185 = 57.29578

2x Pi to 5 dp yeilds 57.29582

I think I must have done it from 4 dp to be so far out.

Bottom line is it doesn't need to be sooo specific as 57.3 is plenty accurate enough for explaining it, but definitely worth noting for the consistency, so thanks, and it's been amended :)
Totally agree ... that is why I said "consistency"

I have a fairly detailed maths background - passed my A-level maths at 15. It irritates me when someone works to say 10 dp (or significant figures) when just one will do or they work to 1 or 2 when a lot several more are needed. You have, in my opinion, got it about right. Do the calculations at 5 or 6 dp and then give the final answer to just 1 - 57.3 degrees.
Thanks :)

I think the line in the article about sums up how I got on with Maths at school...
Remember at school when you’d complain to the teacher about never needing to use trigonometry in real life, well, take it back.
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Re: Understanding Milliradians

#9 Post by TattooedGun »

Polchraine wrote:And what about adding Gradians to the mix? 1 gradian = pi/200 radian
I hope you're being facetious...

*Looks up Gradians*

/Mind blown

Luckily, there's no significant usage to a gradian when referring to Rifle Sights... at least not to my knowledge....
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Re: Understanding Milliradians

#10 Post by meles meles »

Maybe Polchraine cleans the pie off his teeth with steradians...
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