I'm wondering if maybe there is some kind of contamination going on. Right before I coat mine, I put about 5-6 pounds of boolits in a small plastic coffee can and pour in some fresh acetone, shake really well, then drain into another container. After draining well I spread them on my wire cooking tray and put under a fan for about 5 minutes to dry. Next I dump them into my plastic mixing bowl and coat them, dump them back onto the mesh cooking tray and put back under the fan for the drying process.
I then repeat for the other 3 trays since I rotate through 4 trays at a time. I reuse the acetone from the first batch to rinse the other 3 batches and dispose of it after the 4th use. The used acetone usually has a slightly discolored tint to it.