Accuracy of Electronic Targets

[goodi]

Not wishing to hijack the 1000yd moving backer discussion , I noticed that ET's were being referenced.

Have any individuals or clubs actually conducted dedicated accuracy testing of ET's? (ie actual group size and shot position compared to computer nominated group size and shot location coordinates etc)

If so, would they be prepared to detail the testing procedures and results, including the make of ET and the distances in which testing was conducted.

cheers
goodi

 

[INTJ]

@newbieshooter

 

[41magnut]

 

[Comandante]

Depicted here is a 300yd. 2 man squad , F Class target fired on March 6, 2022. The match was an NRA registered match and shot using the Silver Mountain Electronic scoring system. To mitigate defacement of the X ring, all shooters use a 2 moa elevation offset. My squad parter and I both shot F open class. The Target depicts 120 scoring shots and 22 additional sighters. Aggregate scores were 590/28x, and 581/19x. Hope this photo will help you begin your E Target accuracy assessment,

 

[Cfshooter]

always wanted to know myself.

 

[Warren Dean]

Not to be picky, but that is Keith Glasscock.

 

[Cburlette]

It depends on the quality and the rigidity of the frame. For every millimeter the sensors are off the shot will move by 1/2 mm. It should be noted that the magnetic sensor bases on the Shotmarker have at least 5mm play each. Other factors like side to side and fore and aft movement will affect shot placement as well. Depending on how much effort is put into zeroing the target, shots may or may not show up where they actually impact. The system itself should be capable nearly perfect measurements, it’s the human factor that affects accuracy.
Craig

 

[newbieshooter]

Thought the 1000-yard backer discussion was geared toward using an ETarget to count shots and showing where multiple shots/single holes were located?

I just put together my ShotMarker recently for load development work. Used the video series from @F Class John to help me get started. Friend asked the other day, "how accurate is it?". I decided to shoot a few groups, physically measure the groups on the paper target (like you would at a BR match) and compare the measured group sizes to the ShotMarker group sizes.

Placed plain white paper on my Shotmarker coreplast board. I put three (3) different 3-shot powder charges thru the ShotMarker (600 yards).

I measured the each of the 3-shot 'groups' on the paper target (as well as the combination of 2 3-shot powder charges = 6 shot group [shots 4-9]) using a Neil Jones measuring tool - the same tool used at BR matches (to measure groups).


Here are the actual bullet holes/groups shot on copier paper placed on top of the ShotMarker coreplast backer. I then measured the groups/distances with the Neil Jones tool (hard to get precise HeightxWidth since there's no bullet hole to center on) (groups measured several times and averaged):


Here's what ShotMarker displays:




Notes:

• ShotMarker shows shot #4 slightly to the right of #9. Target has #4 slightly to the left of #9.
• There seems to be more overlap of shots #5&6 on ShotMarker than target?
• I have some experience with it - but I am no expert using the NJ tool. Tutorial here.

These are my own initial observations with my ShotMarker system - remember I just got it up and running so I'm still new at this. For my personal load development use, this is more than sufficient. YMMV

Other AS references:

IBS Target Question

Does IBS allow scoring by any of the electronic target systems? Thanks in advance!

forum.accurateshooter.com

How do you evaluate precision - eTargets

Having seen several discussions, and participated in many of them regarding eTargets, I noticed that none of us seem to be on the same page on what to measure in regards to their accuracy. The NRA rules require: • 10.17.1 Electronic Target Requirements- Any electronic target system that meets...

forum.accurateshooter.com

Testing E Target Accuracy

Buy a roll of opaque cooking paper or grease proof clear. Make a square to cover the aiming mark divide in to quarters with a pen line. Place a new aiming mark on the ET at a medium to long range. Fire three rounds into each quadrant of the aiming mark with just two of the total number as close...

forum.accurateshooter.com

 

[6bra1k]

Thought the 1000-yard backer discussion was geared toward using an ETarget to count shots and showing where multiple shots/single holes were located?

I just put together my ShotMarker recently for load development work. Used the video series from @F Class John to help me get started. Friend asked the other day, "how accurate is it?". I decided to shoot a few groups, measure and compare.

I put three (3) different 3-shot powder charges thru the ShotMarker (600 yards). I measured the 'groups' using a Neil Jones measuring tool - the same tool used at BR matches (to measure groups).
View attachment 1325024 View attachment 1325026

Here's what I measured with the Neil Jones tool (hard to get HxW since there's no bullet hole to center on) (groups measured several times and averaged):
View attachment 1325051

Here's ShotMarker:

View attachment 1325064

View attachment 1325065
Notes:

• ShotMarker shows shot #4 slightly to the right of #9. Target has #4 slightly to the left of #9.
• There seems to be more overlap of shots #5&6 on ShotMarker than target?
• I have some experience with it - but I am no expert using the NJ tool. Tutorial here.

These are my own initial observations with my ShotMarker system - remember I just got it up and running so I'm still new at this. For my personal load development use, this is more than sufficient. YMMV

Other AS references:

IBS Target Question

Does IBS allow scoring by any of the electronic target systems? Thanks in advance!

forum.accurateshooter.com

How do you evaluate precision - eTargets

Having seen several discussions, and participated in many of them regarding eTargets, I noticed that none of us seem to be on the same page on what to measure in regards to their accuracy. The NRA rules require: • 10.17.1 Electronic Target Requirements- Any electronic target system that meets...

forum.accurateshooter.com

Testing E Target Accuracy

Buy a roll of opaque cooking paper or grease proof clear. Make a square to cover the aiming mark divide in to quarters with a pen line. Place a new aiming mark on the ET at a medium to long range. Fire three rounds into each quadrant of the aiming mark with just two of the total number as close...

forum.accurateshooter.com

YES BUT
you did not measure groups, just remeasured what the system said....so it does no tlie to itself, but how close to ACTUAL HOLES FROM REAL SHOTS

 

[XTR]

YES BUT
you did not measure groups, just remeasured what the system said....so it does no tlie to itself, but how close to ACTUAL HOLES FROM REAL SHOTS

This has been flogged to near death in thousand post threads.

It depends.

Rigidity of frame
Calibration of system
distance of the impact from acoustic center
and...

WIND!

The sensors use the shock wave to locate the shot based on arrival time at the sensors. Wind from one direction or another shifts the timing based on it's angle and speed. Significance of the variation is based on your expectation of accuracy.

 

[6bra1k]

This has been flogged to near death in thousand post threads.

It depends.

Rigidity of frame
Calibration of system
distance of the impact from acoustic center
and...

WIND!

The sensors use the shock wave to locate the shot based on arrival time at the sensors. Wind from one direction or another shifts the timing based on it's angle and speed. Significance of the variation is based on your expectation of accuracy.

br is more precise than ftr....that expectation
thanks

 

[XTR]

br is more precise than ftr....that expectation
thanks

There are more than a few of us in the F class game who understand that these systems are not ready for prime time; however, 75% or more of the participants are thrilled that they don't have to pull targets and that they got a score. A point or two one way or another doesn't make any difference to them, thus these things have spread faster than Omicron. In fact there are more than I care to think about that would pass on matches if the ranges that have gone to e-targets took them out of service. (basically we're f'd, the NRA limp wristed the rules on the rollout and now we're infected)

 

[XTR]

In BR they would be a fine system to verify shot count. Yes, there are issues with etargets missing shots, but the coincidence of an etarget missing a shot and a shooter getting a double at long range would be exceedingly low. You wouldn't ever have to look at the e target data till someone had a questionable group.

 

[INTJ]

YES BUT
you did not measure groups, just remeasured what the system said....so it does no tlie to itself, but how close to ACTUAL HOLES FROM REAL SHOTS

Looks to me like he hand measured the groups size of the paper targets?

 

[Warren Dean]

 

[chkunz]

I shot seven ten-shot groups from bench rest at 100 yards to compare my hand calculations for mean radius and extreme spread to the ShotMarker Electronic Target system group analysis. The results obtained with the SM ET system for group analysis for mean radius and extreme spread compare favorably with my measurements made by-hand on paper targets using dial calipers and graph paper. The differences in these two methods are probably within my ability to make the measurements on paper. Based on these favorable results I plan to use the SM ET system for future load development and group analysis. You can do this test yourself and decide if it is acceptable for your application; you will need to give some attention to getting a good, rigid and true frame. I would not recommend using this in strong wind but I normally do group testing only in light wind so that is not a problem.

 

[chkunz]

It depends on the quality and the rigidity of the frame. For every millimeter the sensors are off the shot will move by 1/2 mm. It should be noted that the magnetic sensor bases on the Shotmarker have at least 5mm play each. Other factors like side to side and fore and aft movement will affect shot placement as well. Depending on how much effort is put into zeroing the target, shots may or may not show up where they actually impact. The system itself should be capable nearly perfect measurements, it’s the human factor that affects accuracy.
Craig

I just checked mine and they are much closer than the "at least 5mm play" that you quote. Also, your statement that "for every millimeter the sensors are off the shot will move by 1/2 mm" may be correct, but it would be good for the manufacturer to give his thoughts on this, such as is this a bias error or a random error or something else. I am in no way being critical of your knowledge or experience, this is how we learn. I try to test for myself where I can but I am not an expert on the electronics. Best wishes.

 

[chkunz]

Not wishing to hijack the 1000yd moving backer discussion , I noticed that ET's were being referenced.

Have any individuals or clubs actually conducted dedicated accuracy testing of ET's? (ie actual group size and shot position compared to computer nominated group size and shot location coordinates etc)

If so, would they be prepared to detail the testing procedures and results, including the make of ET and the distances in which testing was conducted.

cheers
goodi

I did considerable accuracy testing at 100/200/300/600 yards with the ShotMarker system and my biggest challenge was getting the electronic target congruent with the paper target that I was comparing to. I wrote a report but concluded that the congruency error was of the same order of magnitude as the electronic target error and then there were my measurement errors (small but not zero), my frame construction errors (small but not zero), etc. On the other hand the human errors for the pit crew were near zero (humor). Anyway, my test results satisfied me that the system was good enough for my application.

I am not saying that electronic targets are good enough to determine the national champion but the human error in the pits is eliminated and that is no small consideration.

 

[Jeff Porter]

I dont shoot BR but using e targets to count shots is a good use for it.
The closed microphone systems are more precise and less affected by the factors listed previously but they are heavy and costly compared to an open mike system like SMT or SM. For a game like BR those would be a better choice but I can sense a strong resistance to using any e target for a group size score.

But....For F class or sling shooters.... You cannot have your cake and eat it too... You pick one or the other. As shown above, the 2 MOA offset saved the aiming point on the target and the shooters all shot X's and 10s on the E target while out in the 7 ring of the paper. You cannot put a paper target up on a target that has not been calibrated to that specific instance of paper target application to the backer and compare paper to electronic. The paper bull is just an aming point - the display from the system is your basis for wind calls and scoring. It does not matter if it breaks the line on the paper and shows out on the display. You are only using the display.


BTW - the e targets mark the center of the bullet and then includes the caliber in the display calulations of the point of impact and the score as a function of distance to the center. So if you set everyone to .30 cal then there is no advatage to shooting a fatter bullet.

 

[Warren Dean]

With open mics being a trouble spot, I wonder if anyone has tried some sort of shroud around the outer half of the mic and put some sort of thin foam inside to reduce sound reflection. Might work.