If I get the time I may revisit the WLR/Varget thing in some newer rifles I've acquired since I established my preference a while back. New component lots too.

Components do change. I have two lots of RL15 that are different densities. On the same setting of my Redding BR30 one throws 44 grains and another throws 45.5 grains. My chrono is on the fritz, so I haven't compared what two like volume, different weight charges will do.