You guy seen this yet? ONTarget, measures groups...

K

Keith Skjerdal

Member
You guy seen this yet? On Target, measures groups...

and pretty good too. I tried it against some comp measured groups and it's good, within a thou! Here's the link to a thread in Rimfire and has the examples and links to the software. They say it is even better with a scanner, but you can measure digital pic groups too, you just have to tell the PC the size of a known distance, like 2" on the target. The larger the "set reference" tool distance the better the measurements and bullet hole sizes.

http://www.benchrest.com/forums/showthread.php?t=50209&highlight=OnTarget

The guy that wrote it is even on this board and in this thread above - Jeff Block aka Jeff59 !!

or you can just go get it and try it at http://www.ontargetcalc.com/
 
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I down loaded it but can't find the cord to my scanner. I have a target here that I can't wait to try it on. Will have to take a digital pic of it and go that way. Will let you know how it works. Getting ready to head to Tacoma so will be next week....Tony
 
I've downloaded and installed it but haven't used it yet. My first thought on measuring was to fabricate an easily readable scale to place on the target when taking the picture. That should facilitate calibration. Now I need to do it to prove it. :rolleyes:
 
i'll use it.

its good for me.
measures smaller than my caliper.
newly rebarrled rem 700 #9578x from shilen.243 to hart.308 measures .851rather than caliper at .848moa.
i'll wait to get home to measure with scanner.
it will settle down into <.5 with laddering and reskimming a boyd's.
 
well it worked for two targets then quit, i can not open it up now, seems quirky.
 
A new version of OnTarget has been released.

The reported problems in the old version have been fixed and there are several new features including exporting data to a spreadsheet and defined point of aim. Go to the Features page for more info. There's also a link to a short demo video on the home page.

Here's the link: http://www.ontargetshooting.com

Jeff59
 
Jef, it would be real nice if the OnTarget could measure 300 meters targets... It would make all the ISSF shooters happy!
 
LRCampos said:
Jef, it would be real nice if the OnTarget could measure 300 meters targets... It would make all the ISSF shooters happy!
Click to expand...

I'll be developing the next version of OnTarget later this year. It will have the option to display all measurements in either standard or metric.

For now scroll to the top of the target distance combo box and select the "custom yd." entry. Then type in "328" (300m = 328yds). All of the MOA calculations will then be done using 300 meters as the target distance.

The "Hole Size" field works the same way if you want a circle size that isn't listed.

Jeff59
 
How accurately can this measure "one hole" groups of 5 or 10 shots where individual bullet hole locations are indistinguishable?

+/- what?
 
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Sonof A. Gunn said:
How accurately can this measure "one hole" groups of 5 or 10 shots where individual bullet hole locations are indistinguishable?

+/- what?
Click to expand...

All of the calculations in OnTarget depend on the circles being positioned correctly over the bullet holes. Therefore, if you can identify enough of the edge of a bullet hole to accurately place the circle the calculations will be correct. If the middle of the group is shot out from several bullets passing through then you would not be able to accurately place all of the holes. In this case the group center cannot be accurately calculated. The average distance to center and group offset calculations will not be correct because they rely on the group center calculation. The max spread for the group will be correct since it does not.

The maximum theoretical precision of the program is +-.001". Realistically it all depends on how well you position the circles over the bullet holes.

I shot the target below with a .38 special and these two holes had very clean edges so they make for a good example. I scanned this target at 600dpi. The holes measure .245" even though they were created by a .357" bullet. I can barely see the mark made by the actual edges of the bullets. I measured the group several times at varying zoom levels and the calculated CTC was .292"-.294" each time. In this picture the hole on the right appears to be too far to the left resulting in the lower measurement. At the highest zoom level the holes were about 8" across on my screen, at the lowest soom about 1.5". I can't detect any error when I measure these two holes using my standard calipers.

Here are my suggestions for best precision:
Use a high resolution scan (300-600dpi) so the holes will be clear when you zoom in.
Zoom in as far as possible so you can place the circles accurately over the holes.
Set the "Hole Size" in the program to match the size of the holes in the target, not the caliber of the bullet. It will be easier to position the circles accurately.

Let me know how things are working for you.


2shot.jpg


Jeff59
 
I’ve been playing with this since Jeff released the first version and I couldn’t be happier with the results. I’ve scanned literally hundreds of targets and remeasured them in various ways with the result being accuracy within .001” to .003”. That includes optical comparators with scribed circles, magnifiers, ect. As an example, if you compare the accuracy of this program to a common means of measuring edge to edge used by many non competitive shooters with calipers, you’ll be very surprised how inaccurate the caliper method is. I was called out on another forum for posting my results….so make your own observations and determination.

Based on my testing thus far, it wouldn’t surprise me to find the accuracy of this program within the same limits as those used to measure record targets. Maybe somebody should investigate if that’s true….I don’t know for sure. Think of the side benefits too: Results could be emailed to participants in a match which included the actual pics of the targets and the measurements used to determine both the group and agg size. If nothing else, this is a great way to keep a record of your testing and load comparisons and share them with anybody who has an email address, post on a forum, etc.

I’ve also used it in some unconventional ways too, such as double clicking on the same hole based on either the POA or the calculated group center to get the numbers to determine AGR (Average Group Radius). It’s a hell of a lot easier than plotting these holes on a Cartesian plane for input into AGR software.

I’m not certain what Jeff’s motives are for writing this software and then giving it away, but he should be thanked for his efforts….I certainly appreciate it! Thanks Jeff. You deserve a pat on the back.

Landy
 
Interesting. I notice two comments/obvious facts posted here:

One is that it works best with larger groups where individual bullet holes are discernible and two, that it's accuracy depends on how precisely (human factor) the circles are positioned on the holes.

This being the benchrest forum, the groups more of concern (at least to me) are the tiny, record approaching (or breaking) "bug hole" groups which the accurate measurement of are more my concern. Cost of attending and shooting in major matches are ever increasing as well as the capability of shooting smaller groups, therefore I'm interested in more precise determination of small group sizes.

I have recently realized how such groups can be precisely measured, however it will require a much more sophisticated target setup actually utilizing electronic & electro-mechanical mechanisms* as well as some possible scanning such as jeff59s program. Many here object to any increase in sophistication (and cost) of the target and I understand their concern. However, progress and change has always occured in this game and perhaps progress at the target is inevitable. At least, I have a way it can be done now; today, and the technology is fairly simple (hey, if I can understand it!). If nowhere else, perhaps the bullet makers could use such a methodology for their QC determinations or others using tunnel or underground ranges.

*Targets allready require the electro-mechanical backer setup, so something more than just paper targets is allready necessary.

What I propose is something I'm sure others here have thought of before so I probably only need mention that a moving backer (either linear or circular) in coordination with a means of recording the time of bullet impact is all that you need. Additionally, I propose the use of a backer material which yields better defined bullet holes which assists in scanning precision.
 
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Landy,

Thanks for the good word.

I released OnTarget as freeware for several reasons, but mainly because I didn't want to charge for an unknown product that someone might only use a few times. If someone really likes the program and uses it a lot they can make a small donation to help cover expenses. Otherwise I just ask that they pass it along to other shooters.


Sonof A. Gunn,

Your idea for a multi layer target to measure small groups is really good. The first layer is used for the group spread and the second tracks the individual bullets. It gives the benefit of one hole groups without having to change your point-of-aim. If the hardware existed it would be a pretty cool software project to tie it all together.


Here's a link to an old article. I wonder if anyone ever expanded on the idea. It seems that with today's technology this could work quite well.
http://www.oehler-research.com/wizard.html

Here's another article about about an electronic scoring system.
Electronic Scoring

Jeff59
 
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On Target Software

Tried it and was very happy. The standard way with the calipers gave me a group of .164, but with better precision with the software it measured consistently @ 131.
 
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