Years ago, I weighed a few charges with my old beam-balance and carried on. Now that I have an electronic scale, made in China, I can be more sure that’s acceptable. Here’s my latest test:
The data are not random. There is clearly clustering probably related to the ADC of the scale. Clearly, out of ten charges there are two that have several times larger deviations from the mean than the others. In the 222 Remington, 1 grain of H4198 powder is worth about 100 ft/s in muzzle velocity, so 0.1 grain is about 10 ft/s. Even my extreme charges are probably OK for target-shooting and almost certainly OK for killing gophers/coyotes.