I cast and loaded a huge batch of 38 boolets today and lubed a few hundred. I was planning to change lubes in my sizer when I ran out the batch that was in it, so when the piston bottomed out I put in a stick of my latest mix (Fryxell's Moly-Graph formula in this case) and resumed sizing.
I never cease to be amazed by how much lube is still hiding inside the sizer even when the reservoir is empty. I would estimate I lubed 200 more boolets before I began seeing the new lube appear in the grooves. Now, in the case of pistol boolets these "in-betweeners" that have a mix of two different lubes aren't a concern, but for rifle boolets there might be enough of a difference that long range accuracy could go all goofy.
With my luck I can imagine shooting perfect groups with the mixed up lube that would never be repeatable. Do any of you rifle shooters segregate the in-betweeners or do all of you completely clean out your sizers when changing lube?