That's the biggest problem we have in measuring our powder. We relate VOLUME to WEIGHT. If you bump around on the bench, the powder packs down so it is more dense. Then the volume is heavier.
I started out using dippers in the 1960's when an Ohaus 5-10 or 10-10 was beyond my dreams cost wise. I got pretty consistent with dippers but I had no other choice. I had a small quantity of powder, ran the dipper through it then swept off the top with a piece of cardboard. That gave the charge no bumping or packing down.
Now, there are so many options available for digital scales, it's no longer optional to use one. If you like the dippers, heck, keep using them. Just verify your charge weight.
I personally recommend the Lyman 55 powder measure. It has three separate volume chambers so adjustment is very precise. It even has a little hammer installed in the front of the housing to tap a consistent amount for every charge. I have 9 powder measures and the Lyman 55 is the best of all of them.
With pistol powders, the burn rate is so fast that it's easy to get into KB territory. Yes......you must have a scale. Please....
You gotta die of something.....It may as well be something that you like!
Loving the Harley idle....potato, potato, potato.