Two vids Aim Small posted that are an interesting watch, testing pellet accuracy at different fps.
https://youtu.be/M7TN0jcXdSU
https://youtu.be/MCZjYM5Yolo
https://youtu.be/M7TN0jcXdSU
https://youtu.be/MCZjYM5Yolo
bandg,![]()
you're right, of course.![]()
More shots will increase the size of a group, so groups with more shots will make our test pellet look worse. Not really telling us what we want to know.
➔ This is inherently the problem with the most common shooting performance measurement:
Even if we have a 20-shot group we're really just measuring TWO shots — the two that are farthest apart, say they are 2" apart. Whether we put the other 18 in a ragged dize-sized hole, or whether they are all spread out over all of 2 inches — the extreme spread measurement method does not tell us.
However, if we shot say 3 groups of 5 shots, and took the average, we'd be on much surer ground with our evaluation of the precision of a pellet.
There are of course other shooting performance measurements: The CEP (Circular Error Probable) or the MR (Mean Radius).
These measurements take every shot into account, and average them out. They do get more trustworthy with more shots per group.
Matthias
Here's an article from the Ballistipedia where I learned this:
http://ballistipedia.com/index.php?title=FAQ
Much more accessible are the articles from Cal Zant's PrecisionRifleBlog.com, just excellet: clear and useful.
https://precisionrifleblog.com/2020/12/12/measuring-group-size-statistics-for-shooters/
Phone apps that measure MR (Mean Radius) are:
—Range Buddy
—TargetScan (using on of around 50 official paper targets the app places all hits automatically with one photo)
—Ballistic-X
—and others