I have been doing small batches of clip on WW in preparation for winter casting. For instance this morning I started with 35 pounds, ended up with 28 pounds worth of ingots and 7 pounds worth of sludge. I'll admit that I start skimming the metal clips at a fairly low temperature for fear of melting a zinc weight (three escaped my careful sorting) and that some useful lead is on that dredge. That puts me at 80% recovery from the initial weight.
What's your recovery rate?