Understanding Milliradians
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- TattooedGun
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Understanding Milliradians
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
http://blog.stegough.com/understanding- ... il-milrad/
Kind Regards,
TG
Re: Understanding Milliradians
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...!
Guns dont kill people. Dads with pretty Daughters do...!
- Polchraine
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Re: Understanding Milliradians
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.
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.
"The trouble with quotes on the internet is that it's difficult to discern whether or not they are genuine." - Abraham Lincoln
Why did kamikaze pilots wear helmets?
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- TattooedGun
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Re: Understanding Milliradians
Thanks,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.
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 :)
- meles meles
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Re: Understanding Milliradians
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...
Badger
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Badger Korporashun
Quidquid latine dictum sit altum viditur.
"Quelle style, so British"
- TattooedGun
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Re: Understanding Milliradians
mmm... pie....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...
Must be hungry...
- Polchraine
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Re: Understanding Milliradians
Totally agree ... that is why I said "consistency"TattooedGun wrote:Thanks,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.
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 :)
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.
"The trouble with quotes on the internet is that it's difficult to discern whether or not they are genuine." - Abraham Lincoln
Why did kamikaze pilots wear helmets?
God loves stupid people, that is why he made so many of them.
- TattooedGun
- Posts: 2518
- Joined: Mon Jul 11, 2011 11:55 am
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Re: Understanding Milliradians
Thanks :)Polchraine wrote:Totally agree ... that is why I said "consistency"TattooedGun wrote:Thanks,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.
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 :)
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.
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.
- TattooedGun
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Re: Understanding Milliradians
I hope you're being facetious...Polchraine wrote:And what about adding Gradians to the mix? 1 gradian = pi/200 radian
*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....
- meles meles
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Re: Understanding Milliradians
Maybe Polchraine cleans the pie off his teeth with steradians...
Badger
CEO (Chief Excavatin' Officer)
Badger Korporashun
Quidquid latine dictum sit altum viditur.
"Quelle style, so British"
CEO (Chief Excavatin' Officer)
Badger Korporashun
Quidquid latine dictum sit altum viditur.
"Quelle style, so British"
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