OnTarget group size calculator
Jeff Block has a new updated version of his OnTarget group measuring software that just continues to amaze me with it's accuracy and capability.
If you have any desire to accurately measure group size or even just scan a target and save the analysis of the target as a graphic file and then in a folder on your computer --- rather than sort thru a pile of old targets when you need the load performance info months later --- this will do a great job.
The repetitive accuracy level it can do is incredible --- very comparable to the much more expensive target measuring calipers like the Neil Jones.
Attached below is a scan I did of a CBA “red” target to check how close it could measure the scoring rings on it. The scan was done at a fairly low resolution of 300 dpi which takes about 9 seconds on my scanner.
Increasing this up to 600 dpi will take an additional 8 or 9 secs and isn't needed unless you like to blow up .308 size bullet holes to over baseball size holes and look at the individual fibers of the target paper.
Inputting the fine cross hair in the center of the .308 size circle shown here --- right on the outside edges of the 9 scoring ring (1.440”) is within a .001” --- I'm amazed they can even print these targets that close to specs.
The resolution you see on your monitor will be a lot better than the image shown below as I reduced the image to only 600 pixels wide and a 60K or so file size so I don't get yelled at by Jeff --- our webmaster for using too much band width. ;)