View Full Version : How to measure MOA

Mr. Pub
February 2, 2000, 03:04 AM
How do you measure moa? Do you lay a ruler on a target and take the diameter or the radius of your bullet hole group? Thank you

George Hill
February 2, 2000, 04:01 AM
Some people do it different ways.
I take the whole diameter.

When your doing this, make sure you Bench your rife. Use lots of sandbags and such to isolate the rifle as much as you can and reduce variables to make sure your shooting the same each shot.
To learn more about Benchrest shooting, you can find a good book about it at your favorite book store (who will have to order it) or visit a club that has some Benchrest shooters. Its a little different from normal rifleshooting - but those techniques will let you get the most out of your long gun.
Also pay heed to your ammo selection... Ammo differences can turn a 2 MOA rifle into a .5 MOA rifle... or the other way around.

"A fear of weapons is a sign of retarded sexual and emotional maturity." - Sigmund Freud

Bud Helms
February 2, 2000, 06:29 AM
I'm not trying to be anal here guys, but aren't you talking about how to measure "group size"?

MOA is a known value at 1.047 inches (i.e., one inch) at 100 yds. :D

??? :p

[This message has been edited by sensop (edited February 02, 2000).]

Mal H
February 2, 2000, 12:09 PM
You're both partially right. One MOA is an absolute. As sensop said 1 MOA at 100 yds is 1.047" (sine of 1 min. of 1 deg. X 3600 inches). To figure the MOA of your measured group, simply divide the group size by the MOA size at the distance you are shooting. For example, if you shoot a .66 group at 100 yds, that would be .66 / 1.047 = .63 MOA.

It's easy to figure MOA at common shooting distances based on the 100 yd figure by simple multiplication or division. You only have to remember one number: 1.047. At 50 yds, it's 1.047 / 2 = .52", at 300 yds it's 1.047 X 3 = 3.14". So if you shoot that .66" group at only 50 yds, it's .66 /.52 = 1.27 MOA.

George Hill
February 3, 2000, 06:00 AM
Mal - Sensop...
Your right.
That is how you measure the MOA.
But the original question was only asking about getting the group sizes...


I mean, if I went around saying I was an Emperor because some
moistened bint had lobbed a scimitar at me, people would put me away!

Mal H
February 3, 2000, 09:37 AM
And the title of the entire thread is ...?

It was my impression that Mr. Pub wanted to know not only how to measure a group but how to relate it to a MOA. Only he can answer what he was actually after.

Mr. Pub you're up....

Mr. Pub
February 4, 2000, 12:48 AM
All of you are correct. I wanted to know how to measure group size and how it relates to moa. One of these days I will master the english language and be more percise in my questions. Been traveling last couple of days. Thank you all for your help.

February 4, 2000, 10:18 PM
I am not a benchrest shooter, but couple friends of mine are definitely world class and they have told me that a group is measured from 5 shots and measured to determine the most extreme spread and then subtract one caliber of whatever you may be shooting. Example: .308 with five shot group which happens to measure at extreme spread of say 1". If you deduct .308 from 1.00 that would be your group size or in this example .692" As you can imagine, this is how you will see some of the group sizes in numbers less than .200 and even some of .100, etc. etc. Very tight groups!!

Bud Helms
February 5, 2000, 07:03 AM
Yes .... that's because if you measure outside edge-to-outside edge (" ... most extreme spread ..."?) of the group you're penalized in your group measurement by one caliber.

Measuring from hole center-to-hole center would give the same measurement, but it's kind of difficult when you have one big ragged hole.