As far as the chart, great idea, but for me shooting the 22.cal would not be feasible. Shoot too many pistols, rifles etc. Some in bulk packages, etc. Trying to keep a chart would drive me crazy. Maybe just too lazy. Shooting a new gun like my Nano was fairly easy. Since I shoot two sometimes three times a week at different ranges, I am focused on time and will just grab a box or two of ammo and rush to the range for a quick session. My hat is off to the fellow that does this. I wonder if he is a Accountant?