What is sub MOA?

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PWC

PWC

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MOA is accepted to be 1" at 100yds. So, desired point of impact +/- .5".
1" circle at 100 yds.
2" circle at 200 yds.
It keeps increasing by 1 every 100 yds.

We measure groups to determine "MOA". Isn't it more correct to say impact at "1 inch at X o'clock", or a "X inch group at X o'clock"?

I don't believe saying "MOA" is as effective as saying "a rifle is shooting into X MOA"

To me, throwing around MOA is as meaningful as saying a horse can run " X furlongs per fortenight".

Just me
 
You are confusing accuracy and precision. They are not the same. MOA is a measure of accuracy, not necessarily where the bullets are impacting. Precision is a measure of how far from point of aim the bullets impact. Most people determine accuracy 1st, (MOA). They can then adjust the sights for precision.
 
Not sure your point.

Sure, when spotting, we care where the hits are to either rezero or hold for wind, etc. But those can be easily changed.

Discussing the inherent precision of a system, what group size it can hold to with particular ammuntion, is a useful measurement. A baseline value to understand the relative precision of a class of weapons, or a make/model and ammo combination compared to others. Etc.


Also while we're calling all into question: MOA is a unit of angular measurement that subtends 1.047" at 100 yds. That is conveniently close enough to 1" we pretend that's what it is, but it is not a linear measurement.
 
If the widest space between hits is 1" (outside edges of holes), you're shooting 1 MOA, or minute of angle (1/60 of a degree of arc), so as long as the hits stay within the bounds of what an MOA is at a given range, that's what you're shooting. One MOA is actually 1.047" at 100 yards, so a MOA grows by about a 1/2 inch per thousand yards, a negligible amount. When adjusting for POI, once click of the scope adjustment will usually move the hit 1/4 MOA .
 
MOA is the manufactured, or after market modified accuracy capability of a rifle.

No one is shooting MOA. They are shooting groups with a rifle capable of shooting MOA.

If they are shooting 1" groups, they have adjusted their sights, ammo, position, breathing, etc. to do so.
 
MOA is an angular measurement = 1/60th of 1 degree, increasing in size as the distance increases. Once we in the military FINALLY got scopes with mil reticles AND 1/10 mil adjustments, MOA terminology was only used to describe the size of a group that was already fired, or the (potential) capabilities of a "system"- (rifle, scope, ammunition).
 
jmr40 said:
You are confusing accuracy and precision. They are not the same. MOA is a measure of accuracy, not necessarily where the bullets are impacting. Precision is a measure of how far from point of aim the bullets impact. Most people determine accuracy 1st, (MOA). They can then adjust the sights for precision.
Click to expand...

Sort of this, lol, except reverse the terms for accuracy and precision. Precision is a measurement of how close multiple values are to each other, while accuracy describes how close a measurement is to the target value. Five shots in the same hole are certainly precise, but may not be accurate if they impact 6" left of the target, for example. Similarly, 5 shots dancing in a wide circle around a bullseye may be accurate, but are terribly imprecise.
 
Jim Watson said:
Group shooting is commonly rated center-to-center.
Click to expand...

I was gong to disagree with a previous statement that it was edge to edge, so thank you.

There are optical devices to determine the centers of shot holes for purpose of center-to center precision.

The bullet hole edges are of course important in terms of touching a scoring ring. That's where accuracy comes in.

If I have a nice precise 100 yard one-inch center-to center group which is 3 inches to the right of the point of aim, all I have to do is move my sights 3 MOA to the left in order to attain accuracy.

If a ship's 16-inch gun can place shots within 200 yards at 22 miles south of the ship, that's its precision*.
But if the target is actually 22 miles to the north, that's lousy accuracy.

Terry, 230RN

* That's 17-18 MOA precision if my arithmetic is correct.
 
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So, desired point of impact +/- .5".
Click to expand...
Not really. The convention is that if all of the rounds in measured groups go into less than 1MOA reasonably consistently the rifle is sub-MOA. There's no real requirement that the groups be centered on the actual aim point. No one would claim that a rifle that puts all its rounds into a 0.5" group at 100 yards every time isn't sub-MOA because the groups are centered 1" high on the target compared to the actual aim point.
To me, throwing around MOA is as meaningful as saying a horse can run " X furlongs per fortenight".
Click to expand...
I agree. Of course I agree because the units used don't mean very much as long as everyone involved understands how to convert them into something that is meaningful to them.

For example, as long as everyone understands that 1MOA is about 1" at 100 yards and about 2" at 200 yards, etc. then it doesn't matter whether we talk about groups in inches or MOA.

Similarly, as long as everyone understands that 2688 furlongs per fortnight is 1 mile per hour, we can talk about speed using either fpf or mph without any confusion.
 
JohnKSa said:
There's no real requirement that the groups be centered on the actual aim point.
Click to expand...

Now let's don't take things too far.
There are a few things we do that call for groups to be centered on the aimpoint. You know, like a real target, with numbers. There are even competitive events where both group size and score on target count. There was a target shown here a while with about a quarter MOA group dead center, 50 5X so he won both ways.
 
For target shooting, being centered on the aimpoint is important, but to classify a rifle as sub-MOA, it's only necessary for it to consistently shoot groups that are less than 1MOA.

It's very common to intentionally zero rifles off the actual aim point at a particular distance to provide a better trajectory over a longer range of distances. A rifle shoots exactly to point of aim at no more than two points downrange due to the way trajectories work. Many people want to use a rifle to shoot over a range of distances without adjusting their scope--a very common requirement for hunting. The entire concept of MPBR (Maximum Point Blank Range) typically involves intentionally zeroing a rifle a measured distance above the aimpoint at a known range (e.g. 1.5" high at 100 yards) to keep the trajectory within an acceptable range of distances from the actual aimpoint over the widest possible range of distances.

Would someone say that a rifle zeroed that way was not sub-moa because it made 0.5MOA groups that were 1.5" above the aimpoint at 100 yards? No one I know would.
 
Two types of competition include shooting for group and shooting for score.
Little brother and I would shoot one five shot match for group size and another with same guns/loads for score.
He'd invariably win the group match, I the score.
Makes ad much sense as arguing about it.
To see what the gun is capable of, under your control, shoot a group. I you need to put meat on the table, you better be able to place your shot.
 
PWC said:
MOA is accepted to be 1" at 100yds. So, desired point of impact +/- .5".
1" circle at 100 yds.
2" circle at 200 yds.
It keeps increasing by 1 every 100 yds.

We measure groups to determine "MOA". Isn't it more correct to say impact at "1 inch at X o'clock", or a "X inch group at X o'clock"?

I don't believe saying "MOA" is as effective as saying "a rifle is shooting into X MOA"

To me, throwing around MOA is as meaningful as saying a horse can run " X furlongs per fortenight".

Just me
Click to expand...
We like saying moa just to bug ya. Lol

I shoot slightly over a half minute at a thousand yards, 6.3 agg over a 6 target span.
 
PWC said:
We measure groups to determine "MOA". Isn't it more correct to say impact at "1 inch at X o'clock", or a "X inch group at X o'clock"?
Click to expand...
Well saying "Sub MOA" tells you the next shot will be less than .5X inches at X00 yards.
Saying "1 inch at x o'clock" tells you nothing about where next shot will go or yardage.
Saying "x inch group at x o'clock" other than using the same variable implies that as range and therefore group size increases it moves clockwise, it doesn't tell you range.
Sure saying "sub MOA at X00 yards" is more descriptive than just saying "sub MOA" but I usually just assume if someone says Sub MOA they mean under 1" group at 100 unless specified.
Although asking "at what distance?" Is a perfectly acceptable question.
I wouldn't assume somebody capable of shooting sub 1" groups isn't capable of centering said group X inches away from center in T o'clock direction.
 
Folks:
precision ≠ accuracy
accuracy ≠ precision

period.

Minutes of angle (MOA), whether 1 or 10 or 0.5, is a measure of precision, not accuracy. Accuracy is getting 10 Xs in a string, regardless of whether it's from a 1 MOA gun or a 10 MOA gun.

shootjeep.jpg

Copyright unknown, original by Bill Mauldin .
 
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Rule3 said:
What is above or non MOA called?, Sub is under, MOA is well MOA so what is outside that?
Other than inaccurate or imprecise.
Click to expand...

Strictly speaking, the opposite of the prefix “sub” is “super” (subsonic vs supersonic), but I don’t think that term is useful to the application.

Im pretty sure sub-MOA was a term that began when the ability to shoot smaller than 1 inch @ groups at 100 yards became a more common thing.
 
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