Why accuracy, not precision?

[Mauser lover]

I hope that even those who espouse the use of the term 'precision' as you define it with respect to shooting, are not actually affected emotionally by the fact that the shooting world chooses to use the term 'accuracy' instead. In fact I not only hope that but I believe it to be true.

Burn the heretics!

 

[rpenmanparker]

I hope that even those who espouse the use of the term 'precision' as you define it with respect to shooting, are not actually affected emotionally by the fact that the shooting world chooses to use the term 'accuracy' instead. In fact I not only hope that but I believe it to be true.

Well I think ya got me there.

 

[wally]

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.

You are a bit too strong in your statement.

In fact I mostly shoot in MCB's high accuracy - low precision regime simply because I shoot lots of old, cheap, milsurp ammo in very good guns. Why? I have fun shooting steel plates and I'd rather ring the plate 5 times for a $1 worth of ammo that once (or less). Solution is very simple -- shoot at larger plates, 3-4 MOA plates with 2 moa ammo is a whole lot of fun! I can take out novices and have them ringing steel at 3-400 yards in no time (typically the first outing) without spending a ton of money on ammo or time reloading.

Most novices are in the low accuracy - low precision regime simply because they haven't quite mastered the fundamentals. I start them out on a relatively gigantic plate 8" at 50 yards, and am of the opinion they learn much faster with the instant feedback of the steel ringing or not. After a few consecutive hits I move them to a sequence of smaller plates and then increase the distance and repeat.

 

[spartandemon]

While like most people say on here, the terms accuracy and precision are used interchangeably to measure how precise a gun preforms, the terms have literal meaning...just like clip and magazine. Because there are actual clips made for rifles and a boxed magazine is exactly that. A gun can be precise and not have accuracy; further more you can change accuracy depending on what you are doing to your rifle externally...like a suppressor. You can change the accuracy, and it’s POSSIBLE to maintain the rifles precision simply by interfering with the rifles harmonics.

However as slang is to society, the same in the gun community, people generally brush their shoulder of literal definitions, generally from ignorance, then habbit until it became a norm.

Generally the exception that has never bothered me has been the suppressor/silencer debate. TECHNICALLY, the official professional title has always been suppressor. However it’s not wrong to say that the device infact silences (or rather reduce) sound. Hence silencer.

 

[Hokkmike]

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.

Precisely accurate !

 

[ACES&8S]

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.

For the same reason we call the engine in our trucks, a motor!

 

[rpenmanparker]

For the same reason we call the engine in our trucks, a motor!

What’s a truck?

 

[denton]

rpenmanparker is correct in his definitions of accuracy and precision in the statistical and scientific fields. Precision relates to spread, and accuracy relates to the position of group center. Lack of accuracy, or bias, is easy to fix. You just adjust your sights. Lack of precision is usually harder to fix. That relates to bedding, barrel quality, etc.

It's important, because if precision is lacking, it is difficult to say with certainty where the long-term group center is. That limits your ability to zero your sights. Get precision first, then worry about accuracy.

The other one term that is often used incorrectly is velocity. When you use a chronograph, you are measuring speed, which is a scalar quantity that requires only one number to represent. Velocity is speed plus direction, and requires three numbers to represent, one each for the X, Y, and Z axes.

 

[ontarget]

Very interesting discussion, but by head started hurting about 5 posts in. I find it odd that no shooters ever speak in terms of CONSISTENCY. You can have the best, most accurate, and precise rifle on the planet but without CONSISTENCY its neither accurate, nor precise. Just my .02

 

[Hypnogator]

Commonly accepted parlance, even though technically wrong. Like writing ".30 Caliber" when you really mean 30 caliber. A .30 caliber bullet would be three thousandths of an inch in diameter. Yet it's so commonly used that even gun writers do it.

 

[denton]

Very interesting discussion, but by head started hurting about 5 posts in. I find it odd that no shooters ever speak in terms of CONSISTENCY. You can have the best, most accurate, and precise rifle on the planet but without CONSISTENCY its neither accurate, nor precise. Just my .02

Consistency is precision.

 

[murf]

No. No it isn’t.

yes, it definitely is wrong. did you make it up, or did you actually get it from a reliable source like sae?

murf

 

[murf]

Consistency is precision.

especially if all your shots land exactly 10 feet from the center of the group. not bad if you are shooting a 3 inch pistol at 1,000 yards offhand. not so much if you are shooting a benchrest rifle at 100 yards. precision has no place in a discussion of shot groups.

murf

 

[Danoobie]

IMO, it's semantics and perception. Not only the person describing the accuracy,precision, and consistency, but the people
reading the posts. Mostly they seem to get their message across to each other, on a given accuracy(etc) issue, so I have to agree
you're swinging at a pitch in the dirt, OP. Case in point, what you call "precision" I call "group accuracy", or a "tight group"...

 

[warnerwh]

I don't know how shooters have been able to communicate with each other accurately all these years regarding how well our guns shoot. I guess we should have been more precise so what we convey to one another is accurate. Maybe I am just tired and missed something but I suspect the term "accuracy" will continue to be used by 99% of us when we talk about precision.

 

[rpenmanparker]

Sure, that's fine. I hope you didn't think I expected anything different than that.

 

[hso]

following a set of simple instructions without much thought to why what they are doing works.

Bingo

 

[PapaG]

View attachment 786455

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.

I made exactly that visual aid when teaching shop statistical process control but used the terms "aim" and "variation". Low variation and good aim make for accurately made useable parts.

 

[Elkins45]

I think it comes down to how rifles have historically been used by non-target shooters. A guy takes out his gun, selects a target and shoots at it it. If he hits it he says "That's an accurate rifle." If he misses after several tries he says, "This gun isn't very accurate."

The Average Joe has always been more interested in accuracy than precision, because if a rifle isn't sufficiently precise then it can never be consistently accurate. Precision is a necessary component of accuracy, but accuracy isn't a necessary component of precision.

 

[rpenmanparker]

I think it comes down to how rifles have historically been used by non-target shooters. A guy takes out his gun, selects a target and shoots at it it. If he hits it he says "That's an accurate rifle." If he misses after several tries he says, "This gun isn't very accurate."

The Average Joe has always been more interested in accuracy than precision, because if a rifle isn't sufficiently precise then it can never be consistently accurate. Precision is a necessary component of accuracy, but accuracy isn't a necessary component of precision.

While it would seem that way, it isn't really so according to the definitions of the terms. The two actually have nothing to do with each other. Perfect accuracy actually can exist in concert with very poor precision. Neither accuracy nor precision are usually considered with regard to a single data point. They relate to a statistically significant number of points. The average of several shots can be right on target although none of them hits it. Admittedly this makes for a useless shooting exercise since the object is to hit the target. It also points out that precision is where the shooter's skill and gun's quality come to bear. Accuracy is just an adjustment after precision is taken care of. The emphasis should always be on precision. Once you have that, then accuracy is easy.

 

[doubleh]

My,my. The world consists of rather "imprecise" humans and thus the mixing of terms that are quite common. Many of us realise this and understand the usage without getting our feathers ruffled. It's just the way the world works and it isn't going to change.

 

[rpenmanparker]

My,my. The world consists of rather "imprecise" humans and thus the mixing of terms that are quite common. Many of us realise this and understand the usage without getting our feathers ruffled. It's just the way the world works and it isn't going to change.

Especially is you don't try to change it.

 

[JTHunter]

Commonly accepted parlance, even though technically wrong. Like writing ".30 Caliber" when you really mean 30 caliber. A .30 caliber bullet would be three thousandths of an inch in diameter. Yet it's so commonly used that even gun writers do it.

Check your math !! One inch = 1.0"; one TENTH inch = 0.1"; one hundredth inch = 0.01"; one thousandth inch = 0.001". Thus, a .50 caliber = 0.5" (half an inch); a .30 caliber = 0.3" (tenths); a .38 caliber = 0.38" (hundredsth); a .357 caliber = 0.357" (thousandsth). On these last two, they are called those caliber DESPITE the fact that neither are actually those dimensions, but 0.355 thousandsth of an inch.

 

[doubleh]

Especially is you don't try to change it.[/QUOTE

I "isn't" going to waste my time. I have other things to occupy me besides beating dead horses and most people simply don't care about the difference.

 

[denton]

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.