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Need Help With MOA????

Might or might not be the best place for this...but here goes.

MOA has me baffled!

I thought I had some grasp of it, but reading on another reloading forum has me screwed up again...

Nautical Miles makes tons of sense to me...1.15 nautical miles = 1 statute mile ...I use it all the time in my boats. I'm not very proficient with math, so that might have something to do with it...

Ok...I thought;
1 MOA at 100yds was just over 1"
1 MOA at 200yds was just over 2"
So on and so forth...

I say "just over" because I don't recall exactly...1.047...or something close to that.


Is that not right?

Of course I get the degrees of angle...use a compass in my boats too...it's the math of it that confuses me.
 
Might or might not be the best place for this...but here goes.

MOA has me baffled!

I thought I had some grasp of it, but reading on another reloading forum has me screwed up again...

Nautical Miles makes tons of sense to me...1.15 nautical miles = 1 statute mile ...I use it all the time in my boats. I'm not very proficient with math, so that might have something to do with it...

Ok...I thought;
1 MOA at 100yds was just over 1"
1 MOA at 200yds was just over 2"
So on and so forth...

I say "just over" because I don't recall exactly...1.047...or something close to that.


Is that not right?

Of course I get the degrees of angle...use a compass in my boats too...it's the math of it that confuses me.

Your MOA is right but your nautical miles --> statute miles is exactly backwards.
 
You are correct, So on and so forth... One degree at 100 yards is 62.838. Divide that by 60 (1 MOA) and it is 1.047 at 100 yards. 600 yards = 6.282 MOA
 
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You got it. For practical purposes 1 MOA is 1" per hundred yards. As you said, actually 1.047 but that only matters for extreme long range.

And yes, a nautical mile is ~ 1.15 statute mile, or 1 knot = 1.15 mph.
 
Let me take a crack at the geometry. If you drew a big circle with a radius of 100 yards, it would have a circumference of 2 *pi * 100 yards or 6.283 * 100 yards = 628.3 yards. One degree of arc then is 628.3 yards/360 degrees = 1.745 yards. This is 62.82 inches. One minute of arc is 1/60 of a degree so 1 MOA = 62.82/60 = 1.047 inches.
 
Might or might not be the best place for this...but here goes.

MOA has me baffled!

I thought I had some grasp of it, but reading on another reloading forum has me screwed up again...

Nautical Miles makes tons of sense to me...1.15 nautical miles = 1 statute mile ...I use it all the time in my boats. I'm not very proficient with math, so that might have something to do with it...

Ok...I thought;
1 MOA at 100yds was just over 1"
1 MOA at 200yds was just over 2"
So on and so forth...

I say "just over" because I don't recall exactly...1.047...or something close to that.


Is that not right?

Of course I get the degrees of angle...use a compass in my boats too...it's the math of it that confuses me.


So what was said that confused you?
 
A circle can be divided into 360 degree. Each degree can be divided into 60 minutes (A minute of arc, or angle is 1/60 of a degree.), and each minute of arc or angle can be divided into 60 seconds. So..for example, a 20 MOA scope base has a forward tilt of 20/60 or 1/3 degree. It is really that simple.
 
A happy coincidence of math is that the value of 1 MOA at 100 yards, expressed in inches can be found by dividing pi (3.141592653589793) by 3.

Most calculators have a π key....
π/ 3 = 1.0471975511966 ... the rest is just more arithmetic.
 
So what was said that confused you?
On the Grendel forum a guys was shooting inch and half groups at 200yds and everyone kept saying he was shooting 2 MOA at 200yds but as I understand it...that would be a 4" group, not 1.5". Plus there was more than one saying it...so it had me thinking I was wrong.

But...they also claim you only need a 12" barrel on a 6.5 Grendel when shooting out to 600yds! I fought a long hard battle over that...they ended up calling me names because I said they would get better velocity from a 20". They really didn't like it when I told them they were wasting powder and loosing a lot of velocity on a cartridge that needed all the help it could get...

But that' another thread!

Thanks guys...you successfully gave me a headache with all the math/arithmetic...
 
On the Grendel forum a guys was shooting inch and half groups at 200yds and everyone kept saying he was shooting 2 MOA at 200yds but as I understand it...that would be a 4" group, not 1.5". Plus there was more than one saying it...so it had me thinking I was wrong.

But...they also claim you only need a 12" barrel on a 6.5 Grendel when shooting out to 600yds! I fought a long hard battle over that...they ended up calling me names because I said they would get better velocity from a 20". They really didn't like it when I told them they were wasting powder and loosing a lot of velocity on a cartridge that needed all the help it could get...

But that' another thread!

Thanks guys...you successfully gave me a headache with all the math/arithmetic...
I have left other forums for reasons like that, name calling and such. There are just some people that know everything and resort to those tactics to get their "right or wrong" point across. BTW a 12 inch barrel is a big handgun...
 
A happy coincidence of math is that the value of 1 MOA at 100 yards, expressed in inches can be found by dividing pi (3.141592653589793) by 3.

Most calculators have a π key....
π/ 3 = 1.0471975511966 ... the rest is just more arithmetic.
Yes, if you do the math in radians the answer luckily comes out as Pi at 300 yards. Good to remember for long range.
 
Your MOA is right but your nautical miles --> statute miles is exactly backwards.
I know what I meant to say it just didn't come out right LOL...dyslexia is the reason I struggle with math...is there a name for knowing what you mean but typing the exact opposite? If there is I got that too!:cool::cool::cool::)
 
On the Grendel forum a guys was shooting inch and half groups at 200yds and everyone kept saying he was shooting 2 MOA at 200yds but as I understand it...that would be a 4" group, not 1.5". Plus there was more than one saying it...so it had me thinking I was wrong.

But...they also claim you only need a 12" barrel on a 6.5 Grendel when shooting out to 600yds! I fought a long hard battle over that...they ended up calling me names because I said they would get better velocity from a 20". They really didn't like it when I told them they were wasting powder and loosing a lot of velocity on a cartridge that needed all the help it could get...

But that' another thread!

Thanks guys...you successfully gave me a headache with all the math/arithmetic...

Some of us specialty pistol guys use short tubes to shoot a long ways. I've got a 14" 6mm dasher I've shot to 1k a bunch and a 18" 7-300 win mag I've shot to 2k. Am I losing velocity compared to a rifle, yes, but it sure is fun
 

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