Try doing a search. I'm pretty sure someone shared his Excel file for that purpose recently. A log book will work, too, of course, but it takes longer to find old data that way. A relational database file like an Access file is ideal, as you can search it on any parameter, but I don't think most shooters need that sophistication. Just use Excel, or the free Open Office Suite's spreadsheet program, Calc, to create a worksheet for each gun (a good place to record the serial number and insert a photo for insurance purposes is in this worksheet). Then record the load data in columns and sort those by bullet or powder or whatever. You can also link the same load among different guns that share them (if you do any general purpose loads). Columns just need to be whatever data you normally check when you load. I like to add which dies I used along with the cartridge info. If you've ever shot out a barrel, you'll want to note which barrel used which loads.
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