Good News

[44MAG#1]

I am posting this in conjunction with the thread "Element Of Chance In Defensive Shooting".
I shot a 10 shot target at 25 yards with my M69 Smith 2.75 inch 44 Mag and here are the results.

The Mean on accuracy 2.2595"
The Median on accuracy 2.470"
The Standard Deviation1.1965" Population
The Standard Deviation 1.2251 Sample

Although it takes some work and ciphering to do a target I believe this is the way to go because it makes accuracy look much better that it is the old way of measuring groups.
Hey I did well.

BTW this is offhand, standing. I find offhand gives more excuse when one does poorly.

[dtknowles]

If you are doing statistical analysis SD means standard deviation.

You are learning the difference between accuracy and precision. Small groups indicate precision, high scores show accuracy. It is accuracy that counts but if you don't have precision you are unlikely to have accuracy.

Tim

[44MAG#1]

If you are doing statistical analysis SD means standard deviation.

You are learning the difference between accuracy and precision. Small groups indicate precision, high scores show accuracy. It is accuracy that counts but if you don't have precision you are unlikely to have accuracy.

Tim
Thank you. Your sharp eye is helpful.
I have neither Precision or Accuracy.

[pettypace]

http://snubbyfest.000webhostapp.com/oneskunk.php?Sd=1.2&Dd=0&N=10000

[dtknowles]

I am posting this in conjunction with the thread "Element Of Chance In Defensive Shooting".
I shot a 10 shot target at 25 yards with my M69 Smith 2.75 inch 44 Mag and here are the results.

The Mean on accuracy 2.2595"
The Median on accuracy 2.470"
The Standard Deviation1.1965" Population
The Standard Deviation 1.2251 Sample

Although it takes some work and ciphering to do a target I believe this is the way to go because it makes accuracy look much better that it is the old way of measuring groups.
Hey I did well.

Said another way on average you missed the target center by 2.25 inches and half the shots were more than 2.40 inches out. If you took 100 shots 99 of your shots would not be more than 5.85 inches from the target center (three standard deviations from the mean). Of course using the standard deviation from a test of only 10 samples to predict the outcome of 100 shots is not meaningful. To make meaningful predictions you should have a larger sample set. Another fallacy in my abstraction of your data is that the shots were centered around the center of the target. If you shots were bunched up say to the right of the center of the target then a wild shot to the left would actually be closer to the center of the target, a bad shot that is good.

A five inch group centered on the target could produce this result or a 2 inch group clustered to one side of the center of the target could produce this result.

Tim

[dtknowles]

Thank you. Your sharp eye is helpful.
I have neither Precision or Accuracy.

Everyone has both precision and accuracy it is a matter of how much. You at least made shots that your could measure. Some people have a hard time finding their shots on the target :-) I was shooting my Ruger Single Six the other day. My best groups were 4 inches at 25 yards. I remembered that gun shooting better than that. I vowed to give it a good cleaning and give it another try.

Tim

[468]

For an old guy who is 40 years removed from his most recent statistical analysis class...

Got a photo of the target?

[44MAG#1]

For an old guy who is 40 years removed from his most recent statistical analysis class...

Got a photo of the target?

Don't have a photo. Could take one but as you know one never reveals how statistics are obtained.
I will say this the target is absolutely terrible for me at 25 yards offhand.
Especially with the wild shot.

[44MAG#1]

More good news. I did another Statistical Evaluation on my same 10 shot target I shot yesterday.. This time I figured from the center of the paper. The Figures are thus.

Mean 2.46"
Median 2.155"
Standard Deviation 1.39 population
Standard Deviation 1.46 sample

I like it.

[dtknowles]

More good news. I did another Statistical Evaluation on my same 10 shot target I shot yesterday.. This time I figured from the center of the paper. The Figures are thus.

Mean 2.46"
Median 2.155"
Standard Deviation 1.39 population
Standard Deviation 1.46 sample

I like it.

I suggest you do a two dimensional analysis of the target using a polar coordinate systems recording both the distance from the center and the clock position in degrees. Then report the results of the clock position (degrees) with the same parametrics, mean, median and SD. :-)

Tim

[44MAG#1]

I suggest you do a two dimensional analysis of the target using a polar coordinate systems recording both the distance from the center and the clock position in degrees. Then report the results of the clock position (degrees) with the same parametrics, mean, median and SD. :-)

Tim

You shoot a target and do that. I love to learn. Knowledge is something one can't have too much of.
Let us know the results.

[44MAG#1]

Going in a clockwise direction the shots degree wise from 0 or the 12 o'clock position is 28, 56, 64, 86, 178, 200, 230, 308, 326, 330.
That is based on the center of the group.

[dtknowles]

You shoot a target and do that. I love to learn. Knowledge is something one can't have too much of.
Let us know the results.

Analysis should be based on the point of aim not the center of the group.

273755

This analysis indicates I should be able to keep them in the black until the cows come home but the points of impacts will be all over the clock. It is a pretty tight group but with strikes high, low, left and right. So this group is both precise and accurate though it does lean a bit low left.

273757

This target I did not run the numbers but the mean would be like 0.28" R and the median would be 0.22" R with an SD like 0.09. We need to skew the circular axis so that we aren't jumping across the 0/360 deg. mark so I would make 9 o'clock 0 deg. and then the mean would be 90 deg. the median would be like 90 and the SD would be like 10. Clearly with this ammo the gun was sighted a tiny bit high.

Both groups have a flyer, might be the shooter or the ammo. probably the shooter pulling the shot since the fliers are high and to the left. Riding the recoil instead of good follow through.

Tim

[44MAG#1]

dtknowles said, "Analysis should be based on the point of aim not the center of the group."
Not necessarily correct. I don't chase my POI with my sights when shooting different loads. To much ammo to waste. I hold as close to center as I can hold and fire the shot. If the load prints off I don't care. If it is a load I decide to use I can sight the gun in with it.
Even then if one sights in with shaded sights as under a covered firing line then he gets in the sunlight the sights and POI can change depending on where the sun is even with the load you sight in with when sights are in the shade.
If no influences bother the sights ever one could do like you say. But it doesn't.
You have to shoot well enough to know about influences on your sighting. People who don't believe it either only shoots in exactly the same situation each time they shoot.
So I find statistically where the center of the group is and go from there. Actually I don't fool with this hooey I just go by group size. No one is going to fool around with this stuff.
If you dont believe the lighting condition isn't an influence talk to some IHMSA shooters that were very good or some NRA Bullseye shooters that have shot in matches that were shot outdoors. Even Elmer Keith talked about it. When shooting different loads I don't care where they print as long as they are on target. The group was 1.125 right and elevation pretty well on.

[dtknowles]

dtknowles said, "Analysis should be based on the point of aim not the center of the group."
Not necessarily correct. I don't chase my POI with my sights when shooting different loads. To much ammo to waste. I hold as close to center as I can hold and fire the shot. If the load prints off I don't care. If it is a load I decide to use I can sight the gun in with it.
Even then if one sights in with shaded sights as under a covered firing line then he gets in the sunlight the sights and POI can change depending on where the sun is even with the load you sight in with when sights are in the shade.
If no influences bother the sights ever one could do like you say. But it doesn't.
You have to shoot well enough to know about influences on your sighting. People who don't believe it either only shoots in exactly the same situation each time they shoot.
So I find statistically where the center of the group is and go from there. Actually I don't fool with this hooey I just go by group size. No one is going to fool around with this stuff.
If you dont believe the lighting condition isn't an influence talk to some IMSHA shooters that were very good or some NRA Bullseye shooters that have shot in matches that were shot outdoors. Even Elmer Keith talked about it. When shooting different loads I don't care where they print as long as they are on target. The group was 1.125 right and elevation pretty well on.

You notice that the two target pictures I posted both had the group size written on the target. When testing ammo, I too, don't adjust the sights if the group is going to be close to the center of the target. I do set up a sighter bull so I can make sure the ammo will print close to the center of the bull. I also shoot fouling shots between ammo strings. I shoot groups when testing ammo to determine the precision of the ammo. When I am testing myself I shoot for score. Miss distance is a good indication of my accuracy which is a combination of ammo and firearm precision and shooting skill. The location of the shots on the target are often helpful in diagnosing defects in technique. Shooting skill has a lot of moving parts and varies with course of fire, type of firearm and sights. Shade or sunlight does not affect point of impact much if you are using a scope or peep sights.

I don't calculate the kind of numbers you were and I think you were doing it as sort of a joke but it can have a real application so I ran some to show how I would do it if I was to do it but like my second target. You only need to use your eyes and mental calculator to get the same or more value when looking at a target.

Regarding your group being centered to the right of the point of aim. That is not necessarily a sight adjustment problems.

SHOTS in the 3 o’clock position:

Here the shooter “thumbs” the handgun. Just as the shot begins, the shooter pushes the right thumb against the side of the frame, causing the aligned sights to move to the right.

SHOTS in the Lower Right Quadrant:

This target illustrates what happens when a shooter’s grip tightens as the trigger is pressed. The shooter’s hand clamps or snatches at the last second. This movement causes the front sight to dip low and to the right, pushing the shots to the 3:30 to 5 o’clock zone.

Doing either of these things in an inconsistent manner will open up your group size.

Tim

[44MAG#1]

Thank you for the instructions.

[dtknowles]

Analysis should be based on the point of aim not the center of the group.

273755

This analysis indicates I should be able to keep them in the black until the cows come home but the points of impacts will be all over the clock. It is a pretty tight group but with strikes high, low, left and right. So this group is both precise and accurate though it does lean a bit low left.

273757

This target I did not run the numbers but the mean would be like 0.28" R and the median would be 0.22" R with an SD like 0.09. We need to skew the circular axis so that we aren't jumping across the 0/360 deg. mark so I would make 9 o'clock 0 deg. and then the mean would be 90 deg. the median would be like 90 and the SD would be like 10. Clearly with this ammo the gun was sighted a tiny bit high.

Both groups have a flyer, might be the shooter or the ammo. probably the shooter pulling the shot since the fliers are high and to the left. Riding the recoil instead of good follow through.

Tim

If I center these two groups on their targets, the top target score doesn't change or maybe even goes from a 46 to a 45. The bottom target goes from a 44 to a 49. Being properly sighted in is sometimes important. In a competition for score the top target beats the bottom target in a competition for groups size it is the other way around.

Tim

[44MAG#1]

Thank you again

[dtknowles]

Thank you again

No, I should be thanking you. Without your post I never would have written any of this and who knows, it might be valuable to someone.

Tim

[44MAG#1]

No, I should be thanking you. Without your post I never would have written any of this and who knows, it might be valuable to someone.

Tim

I don't see how.