I take the data calculated by On Target and put it into an Excel worksheet. Then I add other information such as the powder I used, the charge weight, seating depth, MV, ES, SD etc. I often let Excel help me make a graph of something like MOA vs Charge weight. When I go to the range with 5 or 6 different charge weights and shoot 5 shot groups at each charge weight, the graph produces a graphic which is, to me anyway, a lot more revealing than a matrix of numbers. On the same graph I plot Mean Radius because it is more meaningful than MOA, but it's the devil to calculate. Fortunately, On Target does that automatically and for that reason alone it's worth using. Usually I plot the vertical height as well. The three plots are always revealing. Here's an example:
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As you can see, a charge weight of 102% of max published is obviously the best. I don't know about you, but for me this is a lot better than staring at a bunch of scribbled pencil notes in a spiral bound notebook.
Once I have saved the Excel chart for that test session I copy the information and amalgamate it into one large file for each particular rifle. Then it's easy to see which recipe produces the smallest MOA, to use just one example. By the way, I've developed a formula in an attempt to normalize the MOA so that I can compare three shot groups with five shot groups and/or shots made at 100 yards with shots made at 600 yards, for example. That's what "MOA CORR" means. corrected MOA. The formula is not perfect, but it helps me make sense of my master spread sheet. I can also do things like compare Mean Radius vs date to see if my barrel is wearing out over time. Or, perhaps the groups are getting better over time because my reloading procedure is improving; I doubt if I'm getting better myself, given my age. Anyway, you get the idea.
Once the data is organized you can sort and sift in any way you want to pick the best seating depth for a particular bullet, pick the best powder, pick the best bullet for a particular powder, and so-on. Here's an example of a few rows of my typical spread sheet.
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All this sounds like a lot of work, but it's actually pretty easy. Once I have a load recipe log in M.S. Word, it's easy enough to make another slightly-different one by simply changing the date, recipe number, and a few factors like powder type. Then I take that sheet to my reloading room to use as a reloading guide. When I return from the range, I add the data I collected along with some notes about weather conditions, etc. and I save that recipe file for later reference. Each batch of ammo gets it's own unique file name/number.
The real value comes when you ask yourself a question like this before making "the really good stuff" for an upcoming match: "I can't get my favorite powder at the moment; therefore, which alternative powder and bullet combination gave me the next-best results in the past 90 days or 180 days, or whatever?" A master Excel work sheet will give you that answer in a snap along with your personal recipe reference number. Using that number, you can recall your M.S. Word notes to find the exact components and procedures you used to make that recipe. Time you invested in logging your details will be paid back in spades compared with trying to answer this question by thumbing through a big stack of old targets filled with bullet holes and scribbled notes.
(bad attempt at humor)
