Shotmarker data

[ttfreestyle]

Has anyone shot groups on a shotmarker target and physically measured the groups on paper versus what the shotmarker readout numbers were? Say the shotmarker said the group was 5.0 inches, did it actually physically measure 5.0 inches on the paper and if not how close were they in relation to each other? Thanks for any replies.

 

[RDA72927]

I think you have asked a loaded question. I know folks that have tested and tested, say that it is spot on. I heard from folks that hate E-targets and have tested and tested, say there nowhere close. So I think it depends on what answer you want, because I believe you will get both answers to your question..

Robert

 

[tvaught]

My crystal ball says this thread will turn into a HEXTA vs open mic system bashing. Hopefully it's broken.

In the testing I've done with two different open mic systems they printed within .25" to .75" of the actual paper impact, depending on wind at the target, stability of the target frame, and sensor measurement quality.

 

[sdean]

They are not accurate enough for group shooting Yet!!

 

[Keith Glasscock]

It all depends on the conditions, target rigidity, and a few other factors.

They are pretty close for the most part. If the target is very rigid, the hub is out of the sun, and the wind isn't howling and changing across the face of the target, it is even better.

I do load development on mine. Conditions are conditions, and no one load is going to see a benefit over another.

Hope this helps,

 

[prwhite]

They are not accurate enough for group shooting Yet!!

Or score shooting as well.

 

[ttfreestyle]

It all depends on the conditions, target rigidity, and a few other factors.

They are pretty close for the most part. If the target is very rigid, the hub is out of the sun, and the wind isn't howling and changing across the face of the target, it is even better.

I do load development on mine. Conditions are conditions, and no one load is going to see a benefit over another.

Hope this helps,

Thank you for your reply, I am in the process of compiling data and was curious if anyone else had such data.

 

[chkunz]

Has anyone shot groups on a shotmarker target and physically measured the groups on paper versus what the shotmarker readout numbers were? Say the shotmarker said the group was 5.0 inches, did it actually physically measure 5.0 inches on the paper and if not how close were they in relation to each other? Thanks for any replies.

If you are at the MSM match at AEDC Sunday identify yourself to me and we can compare notes. Or email me at chkunz@bellsouth.net. Clyde the elder.

 

[Alexander-M]

I have been using my ShotMarker (SM henceforth) for about three months, and have compared the data from SM, both the CSV exported report and the target displayed, with the actual paper target. So far, I have been very pleased, as if there are any discrepancies, they are in the order of around 0.07” or less.

Here is an example of how I compare the data from shooting yesterday. I was testing four loads, and setup the SM target with a center for the initial zeroing, and four bulls set at 45°, 4-1/2” from the center. The SM display allows me to see how close I am to the bulls (estimate the location), and I may do some minor scope adjustments along the way. I am not interested in the absolute location of the shots, but rather on how well they group together.

This particular one was the first target I shot after shooting several zeroing rounds, and as you can see below, the first three rounds appeared to be too low, so I adjusted the scope up 4/8-MOA, and fired the remaining seven rounds without any further adjustments.

Just to see how the group may looked like if I had the scope adjusted properly to start, theoretically, I ‘moved’ the first three shots up 1/2-MOA, or 3 inches up. This did not affect the vertical dimension of the group, but made it a bit wider. There was a mild (3-4 mph) breeze from 10:00 o’clock.

In the Actual target, you can see the first sighter, S1, and the last, S6. But when I started the test and aimed at the upper right bull (the one shown), the shots were too low because I had used a higher charge for the sighters.

ACTUAL – I use the traditional methods to measure the distances, and divide by 6.24 to convert to MOA (600 yards).

DISPLAY – To measure the distances on the displayed target, I use the X-Ring diameter as 3-inches, and scale the other dimensions from that.

REPORT – I add one line to the Excel spread sheet to provide the vertical and horizontal spreads, which is very easy to do. To analyze just the seven-shots, I used only those rows of data.

ACTUAL - The Paper Target


DISPLAY - Screen Capture


Excel Data - For 10 Rounds, For 7 Rounds, Comparison




Just sharing . . .
Alex

 

[Crow]

I started a new lot of Varget this week and wanted to see how it compared to the last. Fired three groups (old lot/new lot/old lot) through the Oehler into my ShotMarker to see what the numbers looked like, and found the results interesting.

Only 26 rds total (9,10,7), fired from a shaky bench and no flags at 527 yds . Paid the most attention to the last two groups, using the first group to warm things up.

Group 2 (new lot of Varget)
Grp Size:
ShotMarker: 4.53"
Measured w/ calipers: 4.69"
Difference: .16"
Velocity:
Oehler: 2666
ShotMarker : 2037 (at 527 yds)
SD:
Oehler: 7
ShotMarker: 6.3

Group 3 (old lot of Varget)
Grp Size:
ShotMarker: 4.87"
Measured w/calipers: 4.73"
Difference: .14"
Velocity:
Oehler: 2670
ShotMarker: 2036 (at 527 yds)
SD:
Oehler: 5
ShotMarker: 4.5

Was glad to see the two lots of Varget (purchased two years apart) seemed to have similar performance. Group size measurements were 'close', with ShotMarker penalizing one group slightly and paying a small dividend on the other. Most surprising, I thought, was that the velocity measurement from the ShotMarker at 527 yds corresponded closely with JBM Ballistics calculations.

Edited to correct spelling.

 

[ttfreestyle]

Great info guys , just what I was looking for ! thanks

 

[Alexander-M]

(Partial Quote

I started a new lot of Varget this week and wanted to see how it compared to the last. Fired three groups (old lot/new lot/old lot) through the Oehler into my ShotMarker to see what the numbers looked like, and found the results interesting.

Was glad to see the two lots of Varget (purchased two years apart) seemed to have similar performance. Group size measurements were 'close', with ShotMarker penalizing one group slightly and paying a small dividend on the other. Most surprising, I thought, was that the velocity measurement from the ShotMarker at 527 yds corresponded closely with IBM Ballistics calculations.

Crow,

Did you mean JBM Ballistics calculations?

That's good to hear for Varget. I have not had two lots that were that close in performance - maybe next time?
Alex

 

[Crow]

(Partial Quote

Crow,

Did you mean JBM Ballistics calculations?

That's good to hear for Varget. I have not had two lots that were that close in performance - maybe next time?
Alex

Yes, JBM, not IBM! Darn auto-correct...

I got lucky with the Varget, that's for sure.

 

[chkunz]

I have been using my ShotMarker (SM henceforth) for about three months, and have compared the data from SM, both the CSV exported report and the target displayed, with the actual paper target. So far, I have been very pleased, as if there are any discrepancies, they are in the order of around 0.07” or less.

Here is an example of how I compare the data from shooting yesterday. I was testing four loads, and setup the SM target with a center for the initial zeroing, and four bulls set at 45°, 4-1/2” from the center. The SM display allows me to see how close I am to the bulls (estimate the location), and I may do some minor scope adjustments along the way. I am not interested in the absolute location of the shots, but rather on how well they group together.

This particular one was the first target I shot after shooting several zeroing rounds, and as you can see below, the first three rounds appeared to be too low, so I adjusted the scope up 4/8-MOA, and fired the remaining seven rounds without any further adjustments.

Just to see how the group may looked like if I had the scope adjusted properly to start, theoretically, I ‘moved’ the first three shots up 1/2-MOA, or 3 inches up. This did not affect the vertical dimension of the group, but made it a bit wider. There was a mild (3-4 mph) breeze from 10:00 o’clock.

In the Actual target, you can see the first sighter, S1, and the last, S6. But when I started the test and aimed at the upper right bull (the one shown), the shots were too low because I had used a higher charge for the sighters.

ACTUAL – I use the traditional methods to measure the distances, and divide by 6.24 to convert to MOA (600 yards).

DISPLAY – To measure the distances on the displayed target, I use the X-Ring diameter as 3-inches, and scale the other dimensions from that.

REPORT – I add one line to the Excel spread sheet to provide the vertical and horizontal spreads, which is very easy to do. To analyze just the seven-shots, I used only those rows of data.

ACTUAL - The Paper Target
View attachment 1121151

DISPLAY - Screen Capture
View attachment 1121152

Excel Data - For 10 Rounds, For 7 Rounds, Comparison
View attachment 1121153

View attachment 1121154

Just sharing . . .
Alex

The ShotMarker user manual shows the ability to analyze groups. Did you consider using this feature?

 

[Alexander-M]

The ShotMarker user manual shows the ability to analyze groups. Did you consider using this feature?

Yes. Tapping the screen where the shots are displayed allows such analysis, and you can even exclude some shots by resizing the size of the rectangle encompassing the shots. What I have not figured out how to do is to exclude shots that are interspersed within the other shots.

Thx!
Alex

 

[PatMiles]

Yes. Tapping the screen where the shots are displayed allows such analysis, and you can even exclude some shots by resizing the size of the rectangle encompassing the shots. What I have not figured out how to do is to exclude shots that are interspersed within the other shots.

Thx!
Alex

Email Adam.

 

[Jdne5b]

Yes. Tapping the screen where the shots are displayed allows such analysis, and you can even exclude some shots by resizing the size of the rectangle encompassing the shots. What I have not figured out how to do is to exclude shots that are interspersed within the other shots.

Thx!
Alex

Change those shots to sighters, or hidden. That will exclude them from measurements.

 

[rardoin]

Yup....just tap on the shot number at the top of the screen and select hide and they will be excluded but appears as ghosts on the target background as in the above post by Jdne5b.

 

[chkunz]

I have been using my ShotMarker (SM henceforth) for about three months, and have compared the data from SM, both the CSV exported report and the target displayed, with the actual paper target. So far, I have been very pleased, as if there are any discrepancies, they are in the order of around 0.07” or less.

Here is an example of how I compare the data from shooting yesterday. I was testing four loads, and setup the SM target with a center for the initial zeroing, and four bulls set at 45°, 4-1/2” from the center. The SM display allows me to see how close I am to the bulls (estimate the location), and I may do some minor scope adjustments along the way. I am not interested in the absolute location of the shots, but rather on how well they group together.

This particular one was the first target I shot after shooting several zeroing rounds, and as you can see below, the first three rounds appeared to be too low, so I adjusted the scope up 4/8-MOA, and fired the remaining seven rounds without any further adjustments.

Just to see how the group may looked like if I had the scope adjusted properly to start, theoretically, I ‘moved’ the first three shots up 1/2-MOA, or 3 inches up. This did not affect the vertical dimension of the group, but made it a bit wider. There was a mild (3-4 mph) breeze from 10:00 o’clock.

In the Actual target, you can see the first sighter, S1, and the last, S6. But when I started the test and aimed at the upper right bull (the one shown), the shots were too low because I had used a higher charge for the sighters.

ACTUAL – I use the traditional methods to measure the distances, and divide by 6.24 to convert to MOA (600 yards).

DISPLAY – To measure the distances on the displayed target, I use the X-Ring diameter as 3-inches, and scale the other dimensions from that.

REPORT – I add one line to the Excel spread sheet to provide the vertical and horizontal spreads, which is very easy to do. To analyze just the seven-shots, I used only those rows of data.

ACTUAL - The Paper Target
View attachment 1121151

DISPLAY - Screen Capture
View attachment 1121152

Excel Data - For 10 Rounds, For 7 Rounds, Comparison
View attachment 1121153

View attachment 1121154

Just sharing . . .
Alex

Alex, what etarget accuracy do you think you need for your application for group measurement? Clyde

 

[Alexander-M]

Alex, what etarget accuracy do you think you need for your application for group measurement? Clyde

Now, that’s an excellent question.

If I were to use only the SM display & report for my group evaluations, it would not matter to me how accurate the points of impact were displayed & reported as long as they were consistent from one target to the next and from one day to another. All I would want is to be able to compare how a particular load performs vs. another load.

Since I also use the corresponding paper targets, I can evaluate how close the SM displays & reports are to the actual POI on paper. So far, yes; the SM displays & reports would be sufficiently consistent to allow for adequate group comparisons.

I sometimes setup my aiming bulls away from the target center, and make corrections based on my estimate of where the POI are in relation to the POA. In the example below, I set the aiming bulls at 3:00 and 9:00 o’clock, 4-1/2” from the main target center. I knew in this particular case, the bull at 3:00, that the shots were low, but I did not want to bother the vertical performance, so I made no correction. However, the first round showed that the windage was far off to the right, so I dialed a correction. The second round indicated overcorrection, so I backed off after round 2, and shot rounds 3 through 10 without further correction.

In the targets below, the SM report had a vertical of 2.51" for the group, and measuring as closely as I could, I came up with 2.54" for the paper target. This 0.03" difference is fine for me.





On another note – I believe I have read just every post of every thread posted on the forum on e-target accuracy. I have come to the conclusion that some shooters will never like the e-targets, others deem the e-targets to be adequate for competition (but maybe not for States or Nationals), and others prefer to just enjoy the shooting and camaraderie, and not worry too much whether a shot was e-reported off by a certain fraction of an inch. I am in the last group.

I have shot e-targets at Winnequah-Lodi in 2016 and 2017, several times at Big Piney-Houston (MO), and many times at CIHPRS-Atterbury. I have enjoyed them all, and never questioned whether I should have had a higher (or lower) score – they were as they were.

Alex