Why accuracy, not precision?

[lysanderxiii]

Accuracy means the "average" point of impact is where you aim, that can be easily adjusted by moving the sights.

In order to be "precise" and "accurate" makes demands on the shooter and the gun....

An "accurate gun" is accurate in the hands of a tyro and an expert, i.e., the average point of impacts will be centered on the point of aim, the group just might be a few feet across. But the "accurate gun" may not be precise and accurate in the beginner's hands, whereas in probably will in the hands of and expert.

 

[mcb]

I go away for a weekend of shooting and hunting and you guys are still arguing about this? I don't understand the contention? Precision and Accuracy have well defined meanings in the shooting community that are very similar to the definition used in metrology across numerous disciplines.

 

[murf]

precision has no place in a discussion of shot groups.

Au contraire, mon amie! Group size is precision. The difference between intended and actual average POI of many, many shots is bias. Lack of bias is accuracy. To fix lack of accuracy, you adjust your sights. To fix lack of precision, you float your barrel, lap your lugs, recrown your muzzle, etc.

But words mean exactly what you think they do. So if you want to use accuracy, or precision, or consistency in some particular way, that's up to you. I'm cool with it. Just be aware that novel definitions often create difficulties when trying to communicate.

rather than waste our time with this, i will just say, i disagree with everything you and rpenmanparker have to say on the subject of precision and accuracy.

murf

 

[denton]

rather than waste our time with this, i will just say, i disagree with everything you and rpenmanparker have to say on the subject of precision and accuracy.

murf

I find that perfectly satisfactory. I have no compulsion to get agreement. You seem satisfied with what you have.

 

[mcb]

Sink your teeth into this one: http://ballistipedia.com/index.php?title=Home

 

[Frank Ettin]

....Why do shooters insist on calling precision accuracy? ....

As should now be obvious from this thread, for the same reason some folks insist on calling magazines "clips" and will argue incessantly that they are correct doing so. To quote Humpty Dumpty (Through the Looking Glass by Lewis Carrol):

'When I use a word,' Humpty Dumpty said, in rather a scornful tone, 'it means just what I choose it to mean — neither more nor less.'

'The question is,' said Alice, 'whether you can make words mean so many different things.'

'The question is,' said Humpty Dumpty, 'which is to be master — that's all.'

On the other hand, Confucius said, "The beginning of wisdom is to call things by their proper name."

Personally, I'll seek wisdom.

 

[Doc7]

I am with the poster on page 1 who said that because we have adjustable sights, “Accuracy” is all but meaningless in the context of a shooting rig, and group size / precision rule the vocabulary. A measuring tool may be very precise but inaccurate because the numbers are marked wrong or the threads were poorly created, etc. With a rifle, the only reason it would be not “accurate” would be because the shooter failed to adjust the sighting system properly, and it is very unlikely to have a man and his gun shoot extremely precisely (let’s say 0.8 MOA 10-shot groups) and not have the knowledge and wherewithal to adjust his sights such that his shots were accurately hitting his intended POI.

 

[Doc7]

Also, I will say that at least the OP hasn’t mentioned BEGGING THE QUESTION yet - my own pet peeve.

Begging the question, sometimes known by its Latin name petitio principii (meaning assuming the initial point), is a logical fallacy in which the writer or speaker assumes the statement under examination to be true. In other words, begging the question involves using a premise to support itself.


Examples:
Freedom of speech is important because people should be able to speak freely.

The death penalty is wrong because killing people is immoral.

Ghosts are real because I have had experiences with them myself.

Thus, anytime you’ve ever read the phrase, “that begs the question, ‘.....?’” it was completely incorrect use of the term.

 

[Frank Ettin]

I am with the poster on page 1 who said that because we have adjustable sights, “Accuracy” is all but meaningless in the context of a shooting rig, and group size / precision rule the vocabulary.....

Yet still "accuracy" means what it means, and "precision" means what it means; and they mean different things. Whether the use of the words or the meanings of the words matter will depend on what the topic and purpose of the discussion is.

So if I want to talk about firing my gun so that the bullet will hit a particular spot, I'm interested in accuracy. There may be several ways I can cause the bullet to hit where I want. If the sighting arrangement causes a know deviation of POI from POA, I can adjust the sighting arrangement to change or remove that deviation. Or I can simply change my POA to compensate for that deviation. But how well either of those strategies will work will depend on precision.

Precision decides how well I can know the amount by which POI deviates from POA.

Maybe in certain contexts one concept is more important or useful than the other. But a well rounded shooter understands both terms and uses them appropriately.

 

[rpenmanparker]

Now we are getting somewhere.

I should mention that “begging the question” is a pet peeve of mine also.

 

[ford8nr]

Hey guess what? My wife and I went SHOOTING yesterday. She shot very well first time out this year. Saturday I'm going out to SHOOT a High Power event. No discussions of Precision or Accuracy, adjust your sights and SHOOT.
Here's my last target of the day. Colt Challenger
Accurate or Precise ? Who cares ?

 

[rpenmanparker]

Distance?

 

[ford8nr]

Being the internet,
150yds, weak hand one handed, offhand.

Reality - 12 yds
And I corrected the pistol, it was shot with my wifes Colt Challenger.

 

[hdwhit]

rpenmamparker wrote:
Like in the cases of many such errors, when you confuse the terms, you lose the ability to properly discuss them.

In the sense of discussing the definitions behind the terms, yes.

But, on the other hand, if someone brings me a target with a 1 inch group achieved using one load and another target bearing a 3 inch group from another load and refers to it as "accuracy", I know precisely (pardon the pun) what they are actually talking about and how to start diagnosing the problem. It does not become necessary for that person to use the terms "precision" or "accuracy" correctly nor is it necessary for me to enlighten them as to the distinction between accuracy and precision in order to help.

 

[Bwana John]

If we are going to get stinky about accuracy vs precision.....

How about the speed vs velocity? (Speed being a scaler, and velocity being a vector with both magnitude AND direction)

 

[mcb]

If we are going to get stinky about accuracy vs precision.....

How about the speed vs velocity? (Speed being a scaler, and velocity being a vector with both magnitude AND direction)

Just use a Tensor and you can encapsulate both the vector and the scalar...

 

[rpenmanparker]

In the sense of discussing the definitions behind the terms, yes.

But, on the other hand, if someone brings me a target with a 1 inch group achieved using one load and another target bearing a 3 inch group from another load and refers to it as "accuracy", I know precisely (pardon the pun) what they are actually talking about and how to start diagnosing the problem. It does not become necessary for that person to use the terms "precision" or "accuracy" correctly nor is it necessary for me to enlighten them as to the distinction between accuracy and precision in order to help.

Necessary no. Desirable, IMO yes. Why shouldn’t we all want to learn something new to us every day? Why is everyone so proud of being wrong? Where is the upside of that?

 

[Frank Ettin]

If we are going to get stinky about accuracy vs precision.....

How about the speed vs velocity? (Speed being a scaler, and velocity being a vector with both magnitude AND direction)

Yes, speed and velocity are different. If you mean "speed", use "speed." If you mean "velocity" use "velocity." Why use "speed" if you mean "velocity"? Why use "velocity" if you mean "speed"?

If you don't know the difference, learn the difference. Ignorance really isn't a virtue.

 

[Pete D.]

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.

Reminds me of the confusion of caliber and cartridge.

 

[buck460XVR]

Because MOA IS a measure of accuracy, not precision. Sometimes that we you were talking about do get it right. Kind of like a stopped clock.

From, "OnTarget Shooting"...........“Precision” measures how consistently the rifle places each shot on the target. Precision is measured from the center of each bullet hole and is usually stated in MOA (minutes-of-angle)."

So, who is right? A random poster or a web site dedicated to "precision" shooting?

Does it really matter?

The majority of these types of threads has to do with folks trying to impress others with their knowledge or their superiority. The old, I'm smarter or better than you because I know the right terminology. Lotta folks out there more precise in their shooting than any of us here that use the word "accuracy" to describe it. I've found the word "precision" has become similar to the word "tactical". As for the Confucius thing..... he also says "man who go to bed with itchy butt, wakes up with smelly fingers". Makes about as much sense and is about as appropriate as the other quote in this thread.

 

[rpenmanparker]

From, "OnTarget Shooting"...........“Precision” measures how consistently the rifle places each shot on the target. Precision is measured from the center of each bullet hole and is usually stated in MOA (minutes-of-angle)."

So, who is right? A random poster or a web site dedicated to "precision" shooting?

Does it really matter?

The majority of these types of threads has to do with folks trying to impress others with their knowledge or their superiority. The old, I'm smarter or better than you because I know the right terminology. Lotta folks out there more precise in their shooting than any of us here that use the word "accuracy" to describe it. I've found the word "precision" has become similar to the word "tactical". As for the Confucius thing..... he also says "man who go to bed with itchy butt, wakes up with smelly fingers". Makes about as much sense and is about as appropriate as the other quote in this thread.

I suppose you could use MOA to express group size, and in fact that would be a good idea that I would support. But you know as well as I do, that is not usually the case. Groups size is expressed most commonly in inches or cm at a specified shooting distance. I didn’t decree that. It is just the way it is.

Your complaint about those who would gratuitously educate us in areas we are ignorant reminds me of the old admonishment to children that we associate with Appalachian parents fairly or otherwise: “Don’t get above your raisin’.” How uplifting!

 

[mcb]

I suppose you could use MOA to express group size, and in fact that would be a good idea that I would support. But you know as well as I do, that is not usually the case. Groups size is expressed most commonly in inches or cm at a specified shooting distance. I didn’t decree that. It is just the way it is.

Your complaint about those who would gratuitously educate us in areas we are ignorant reminds me of the old admonishment to children that we associate with Appalachian parents fairly or otherwise: “Don’t get above your raisin’.” How uplifting!

Group size (precision) expressed in linear units at a given range gives the same information as MOA at a given range. They are just expressed in different units.

 

[rpenmanparker]

Group size (precision) expressed in linear units at a given range gives the same information as MOA at a given range. They are just expressed in different units.

Yep.

 

[doubleh]

This thread has been the first debate about the two terms I've ever encountered.

Yesterday while following my wife around the local "we have a quire a bit of everything store" I passed by the magazine rack and noticed two magazines I had never seen or hear of before. One was titled " Precision Rifle Shooter" and the other was " Precision Shooting". I thought they would be interesting but I discovered that, like the subject they are devoted to, they were kind of pricey and I left each there.

 

[rpenmanparker]

This thread has been the first debate about the two terms I've ever encountered.

That actually surprises me. I was afraid I was going over old ground.