Why accuracy, not precision?

[rpenmanparker]

I know better than this. Asking this question will only lead to heartache. I just can't resist.

Accuracy is what you adjust when you zero a gun to hit the bullseye. Precision is how repeatably successive shots hit the same spot or nearly so. The size of a five shot group relates to precision. The placement of the center of that group relates to accuracy. Why do shooters insist on calling precision accuracy? Is it so universal a practice that one should just consider the words to have been redefined for shooting?

And if shooters call precision accuracy, then what do they call real accuracy, i.e. how close to the bullseye a bullet lands?

Forgive this pitiful sinner.

 

[Jim Watson]

As you probably know by now, the word "accuracy" is commonly used in both senses.
Why not? It is not like it is IMPORTANT, like "magazine" vs "clip."

 

[rpenmanparker]

As you probably know by now, the word "accuracy" is commonly used in both senses.
Why not? It is not like it is IMPORTANT, like "magazine" vs "clip."

It is not common to use accuracy in both senses in technical topics and statistics, i.e. in the fields that are based on these concepts and where the terms were defined. Like in the cases of many such errors, when you confuse the terms, you lose the ability to properly discuss them. In other words folks don't know exactly what you are talking about.

 

[primalmu]

I feel like the proper use of "accuracy" is pretty meaningless in shooting. After all, would it be fair to say that a hunter who sights his rifle in 2 inches high at 100 yards has an inaccurate rifle?

True accuracy is an adjustable value based on a shooter's needs and the ammunition they are using. It would be a more useful term if rifle sights/scopes were not adjustable. At least there's the term "precision shooting."

 

[rpenmanparker]

I feel like the proper use of "accuracy" is pretty meaningless in shooting. After all, would it be fair to say that a hunter who sights his rifle in 2 inches high at 100 yards has an inaccurate rifle?

True accuracy is an adjustable value based on a shooter's needs and the ammunition they are using. It would be a more useful term if rifle sights/scopes were not adjustable. At least there's the term "precision shooting."

I can see accuracy applying to that sighting in situation. At least it is referring to the correct concept, the average similarity of POA to POI. Basically accuracy is the mean position of the POIs. Precision is the deviation among the shots.

 

[buck460XVR]

If one looks at their definition, both words are virtually interchangeable. Accuracy is defined as the quality or state of being correct or precise., while precision is defined as the quality, condition, or fact of being exact and accurate.. Don't know where you're going with this, but there ain't much in the pot to stir.

 

[primalmu]

If one looks at their definition, both words are virtually interchangeable. Accuracy is defined as the quality or state of being correct or precise., while precision is defined as the quality, condition, or fact of being exact and accurate.. Don't know where you're going with this, but there ain't much in the pot to stir.

His point is that from a statistical and scientific point of view, those definitions are incorrect (though they do reflect common/colloquial usage).

 

[buck460XVR]

His point is that from a statistical and scientific point of view, those definitions are incorrect (though they do reflect common/colloquial usage).

That was my point, not much pot to stir. Those definitions were from Dictionary.com., so I'm takin' them as accurate enough for our purpose, or am I not being precise enough?

 

[reddog81]

The placement of the group will vary depending on how well the scope is adjusted, wind, velocity, etc. if you can shoot a half inch group 3" inches off to the right it should be relatively to adjust the scope or sights so that you're hitting the bullseye. Most people are concerned about precision because accuracy should be an easy adjustment if you know what you're doing.

Precision isn't a concept many people think about on a regular basis. Right or wrong, accuracy is used for both terms and there is rarely any confusion on the subject.

 

[Hokie_PhD]

It's like people calling an engine a motor. Or worse calling magazines clips.
The English language is a mess created over centuries of mangling other languages and incorporating slang and foreign words into it.

I used to get a bit annoyed about it but there isn't much I can do so I don't worry about it most of the time.

 

[rpenmanparker]

If one looks at their definition, both words are virtually interchangeable. Accuracy is defined as the quality or state of being correct or precise., while precision is defined as the quality, condition, or fact of being exact and accurate.. Don't know where you're going with this, but there ain't much in the pot to stir.

That is a common language definition. I would have thought that shooters would be interested in the technical usage. Not the first time I have been wrong.

 

[PapaG]

I'm going to go with Whelen: only accurate rifles are interesting.
I think, from my days doing statistics in the shop, that you have really two things: aim and variation. Variation determines the size of the group. Aim is where the group hits. Accuracy is a combination of the two. Low variation, proper location equals good accuracy. If you have the ability to hold, aim, squeeze and repeat "accurately".

 

[rpenmanparker]

I'm going to go with Whelen: only accurate rifles are interesting.
I think, from my days doing statistics in the shop, that you have really two things: aim and variation. Variation determines the size of the group. Aim is where the group hits. Accuracy is a combination of the two. Low variation, proper location equals good accuracy. If you have the ability to hold, aim, squeeze and repeat "accurately".

Your post demonstrates the problem. Technically speaking accuracy does not include variation. Variation is precision. But I get it. A gun can be accurate but Imprecise, i.e. it can shoot 10 shots that average out to the point of aim but be all over the place.

Hey, it’s okay. I get that this is not a hill to die on.

 

[mcb]

It's easy to make a precise rifle also an accurate rifle. But an accurate rifle that is not also precise will have one-shot group accuracy that sucks. And the one-shot group accuracy is what counts when your trying to hit something.

 

[ford8nr]

My head hurts.
Except in a scientific word, what does it matter? In laymans terms " is it the gun or the shooter"
On a different note, I've gone to calling them clipazines to avoid confusion.

 

[hso]

consider the words to have been redefined for shooting?

Never!

As you accurately said, precision is about consistency/grouping...accuracy is about hitting the mark.

 

[JohnKSa]

But I get it. A gun can be accurate but Imprecise, i.e. it can shoot 10 shots that average out to the point of aim but be all over the place.

A gun that doesn't shoot to the point of aim (barring some difficulty with the sight adjustment or a significant barrel alignment problem) is neither imprecise nor inaccurate. It is simply a gun with the sights misadjusted.

A gun that can't reliably put a bullet near the point of aim but that sprays them around in a pattern that is statistically centered on the point of aim is neither accurate nor precise. It's just worthless.

 

[mcb]

Precision and Accuracy have well defined meanings in the scientific, engineering, and precision shooting communities. The definition are not hard to understand and work well within the shooting context. Not sure why you would not use them?

 

[rpenmanparker]

A gun that doesn't shoot to the point of aim (barring some difficulty with the sight adjustment or a significant barrel alignment problem) is neither imprecise nor inaccurate. It is simply a gun with the sights misadjusted.

A gun that can't reliably put a bullet near the point of aim but that sprays them around in a pattern that is statistically centered on the point of aim is neither accurate nor precise. It's just worthless.

Well that is a new way to define the terms.

 

[rpenmanparker]

That graphic always puzzles me. The top left appears to me to be imprecise but pretty darn accurate. Those shots average to just left of center...to my eyes.

 

[JohnKSa]

It's not a redefinition, it's merely looking at the problem from a different perspective. One that explains why there is, in general, no strong push in the gun community to rigidly distinguish between accuracy and precision.

 

[rpenmanparker]

I would wager that most folks when zeroing a pistol are depending on the true definition of accuracy. Their shots are likely not precise enough to dictate exactly how the sights should be shifted. It is the “eyeball” average of the three shots that one uses to make the next setting. If you just shot once at a time and immediately moved the sights accordingly, you would be going around in circles all day.

 

[rpenmanparker]

To misquote Tevya from “Fiddler on the Roof”, misusing the terms accuracy and precision is no great shame, but it is no great honor either.

 

[Milt1]

I think most shooters (specially those testing handload) or, possibly those testing different factory offering, go to the range thinking of how accurate they hope their handload/factory loads are. I don't think they go to the range thinking "I hope my handloads/factory loads are going to be precise".

 

[JohnKSa]

I would wager that most folks when zeroing a pistol are depending on the true definition of accuracy.

I would wager that the vast majority of people who manage to zero a firearm didn't do so by relying on specific definitions of precision or accuracy but rather by using trial and error or by following a set of simple instructions without much thought to why what they are doing works.