Welcome to the forum, you'll find lots of great help here.
My 2 cents on your particular situation is that Unique does not consistently dispense well through Lee auto disk measures. I have a good amount of experience with both Unique powders and Lee auto disk measures and my conclusion is that the two should never be used together...
either switch powders or use a different dispenser. Its odd that the dipper is light too though, are you sure that the scale is zeroed?
Hope this helps
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