You rely on your scale for safe, accurate powder changes. Over time, accumulated grit and dust can affect accuracy. A quick test with RCBS Scale Check Weights will tell you if your scale is reading correctly.
Set of 60.5 grains for powder charges
2x20, 1x10, 1x5, 2x2, 1x1, 1x.5
510.5 grains for bullets, cases and powder
1x200, 2x100, 1x50, 2x20, 1x10, 1x5, 1x1, 1x.5