Good Accuracy. Bad Precision.

Congratulations on the new rifle!

Accuracy and Precision seem to have been covered above. In any event, if you are getting consistent outliers low and left shooting off a bench and bag, I’d want to work on trigger pull consistency. One old trick is to balance a coin on the barrel (assuming round not octagonal) out by the muzzle and dry fire. When you stop knocking it off, you are probably using a smooth and consistent pull. Should work with a Savage in 17 HMR.

Turkeytider said:

Started getting acquainted with my new to me Savage .17HMR bolt gun. Fun to shoot. Accuracy at 100 yards has been acceptable to me, averaging sub-MOA, but precision, well, not good. A general pattern seems to be low and left. Just have a hunch I have inconsistencies from shot to shot in my shooting form. Gun is zeroed to 100 yards, cold bore shot this morning at the range was dead center. Any suggestions would be greatly appreciated. Thanks.

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Sounds like trigger control

LoonWulf said:

And i thought I was a Gun Nerd.....
Yall make me feel new....

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No kidding. Glad I don't own anything that's either accurate or precise, or I'd be confused as hell. Since it doesn't apply to my stuff, I can ignore all the big words.

taliv said:

Walkalong, you’re shooting matches in the precision rifle series, not the accurate rifle series. You need to bring a precision rifle, which is capable of shooting small groups. The competition is about how accurate you are with your precision rifle.

It’s not a competition about how precise you can be

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Absolutely my favorite irony in the shooting sports world… “Accuracy games” are often scored more heavily toward precision, measuring raw and agg group sizes, and then the “precision” series is all about just being accurate enough to hit large targets.

Walkalong said:

I have always seen that as the OP does. Accuracy is tight groups while precision puts the group where you want it.

I know, we disagree.

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Yep, that’s backwards.

So a person could shoot accurately with a shotgun, but bird shot patterns aren't very precise.

Turkeytider said:

…at 100 yards has been acceptable to me, averaging sub-MOA, but…A general pattern seems to be low and left.

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If a firearm is consistent in bullet placement but the location of the impacts are low and to the left of where you want them, you need to move the sighting device accordingly.

Something like this should work.

Walkalong said:

We need accurate rifles to help us precisely place rounds downrange.

I just look at it different than the engineer who needs to be technically correct.

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And as an engineer by profession I usually don't get pedantic about these terms either. If you tell me in a hunting thread your most accurate prairie dog rifle is X and shoots sub MOA at 300 yard I am unlikely to correct or even comment on the terminology. I know what you mean, that rifle X is both precise and accurate enough to reliably hit a prairie dog at those distances.

Only when we start a discussions specifically about group size and and the ability to center the group on the point of aim, and repeatability, especially at greater ranges, do the correct technical definitions of precision and accuracy become more necessary to the conversation.

Howland937 said:

So a person could shoot accurately with a shotgun, but bird shot patterns aren't very precise.

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Right. American Rifleman reports on shotguns show where the center of the pattern is relative to the middle of the pattern board. Trapshooters are very particular about pattern placement, like 70/30% above and below the bead for the rising targets.

These days, the "riot gun" is not considered a "scattergun", we are told we should not shoot at an opponent farther away than where all buckshot pellets will hit him. So accuracy matters there, even precision; I saw one brand of ammo criticized because it tended to throw one .33 pellet out of the otherwise tight pattern.

mcb said:

Only when we start a discussions specifically about group size and and the ability to center the group on the point of aim, and repeatability, especially at greater ranges, do the correct technical definitions of precision and accuracy become more necessary to the conversation.

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This. When the discussion is the differentiation of the two, (score vs. aggregate or raw group), the differentiation matters.

My wife sends me to the store occasionally, and the shopping list will say “Kleenex,” but I know she doesn’t want “Kleenex’s,” she wants “Puffs” with lotion. The accepted colloquial moniker isn’t correct, but it’s often accepted - until it comes time to accurately differentiate and buy the right facial tissues. When I was working for a shop and someone asked for a “clip,” for their Glock, I used to have to ask what brand and model, because colloquially “glock” was synonymous with “pistol”. Spend time dining out in the South and you might be asked what kind of “coke” you want with supper, and “Pepsi” is a legitimate answer. Slang is slang, and this pair is commonly misused - I just don’t see sense in standing up and continuing to call magazines “clips,” once you know the difference. Same with P & A - at least within the context of conversation in which they’re differentiated.

I read this entire thread and came away with nothing but nonsense.

You need to check your rig over carefully. Loose mounts? Scope adjusted near the extreme of the range? Parallax? Bedded and floated? Decent trigger? Then check your form from one session to the next. My rifles are sensitive vertically to how they are rested. And sensitive to how well I get in position and pull the trigger.

Accuracy and precision? You need both to hit anything.

CoalTrain49 said:

Don't you mean accurate measuring tools.

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Doesn't "precision" when referring to measuring tools also mean "accurate". I certainly hope my micrometers which are precision measuring tools are accurate. Of course I have a way to check if they remain accurate.

I'm sure my use of the terms "precision" and "accuracy" have changed multiple times over the years. I've settled on "this rifle can shoot tight groups and I can hit targets with it."

All we need now is a rehash of the trope "This rifle shoots better than I do."

doubleh said:

Doesn't "precision" when referring to measuring tools also mean "accurate". I certainly hope my micrometers which are precision measuring tools are accurate. Of course I have a way to check if they remain accurate.

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In that vein, I would take accurate to mean getting the correct reading of .25" when measuring something that is one fourth of an inch. Reading .0025 of something that's 25 ten thousandths of an inch would be pretty precise. Precision is why surgeons use scalpels (or lasers) instead of Buck knives I suppose.
Could be naive on my part though.

I check my electronic scale with standard weights and have to adjust the accuracy occasionally. The precision is normally quite good. Same with my digital calipers.

I have an engineering degree and worked in that field for 40 years. They won't be changing the definition of either of those terms anytime soon in academia.

But y'all use what ever terms suits your fancy. It has to feel right when you say it, especially if you're from Missourah.

Howland937 said:

Precision is why surgeons use scalpels (or lasers) instead of Buck knives I suppose.

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The surgeon made a very precise cut but unfortunately if he amputates the wrong limb, his accuracy is in the toilet.

Howland937 said:

So a person could shoot accurately with a shotgun, but bird shot patterns aren't very precise.

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Open cylinder would be less precise than full choke. Lol
Actually the shotgun would be treated just like a rifle as regards precision and accuracy, but with the shot mass treated like a bullet.
Think of it like this -
bent barrel = poor accuracy
Loose barrel = poor precision

you need precision tools to measure accurately .

If cold bore shots are at POA and POI changes on hot shots then there could be a cleaning issue. A carbon ring near the chamber can cause those results as can slight changes in the rifle as it heats such as bedding. Maybe that is all your ammo can give you. Not sure.

Since this seems like a train wreck anyway, I don’t suppose anyone would like to discuss @Turkeytider ’s shooting form?

Turkeytider said:

Just have a hunch I have inconsistencies from shot to shot in my shooting form.

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