It is neat when you find a good barrel, trigger, rifle position, case prep method, good case brand, primer & powder lot combo that delivers "1/2" groups with regular repeatable reliability.
It is going from "1/2" down to "1/4" groups and leaving your rifle in a fixed "bench rest" position where all this tiny stuff "could" matter.
Here is the tool:
https://www.brownells.com/reloading/meas...-prod34014.aspx
For me... 0.5 - 0.7 makes me very happy. I don't have to turn case necks, anneal or order custom specialty tools.
If i did not have kids i would likely be into all that stuff.
