So, I finished up a batch of 5.56 ammo today with H335 powder, and decided to make a little .308 with some RE-15. As usual, I emptied the powder measure of the H335, operated the handle a few times when empty, and tapped it a few times to get all the stray powder grains out. Then I switched powders and started loading with Re-15. About halfway through, I noticed a few small ball grains mixed in with the stick powder. Furious, I inspected my powder measure. Apparently, not only does it leak a little from the side (which I knew, but had determined that it was an insignificant amount of powder), but it also holds some powder deep inside and continues to leak it as it operates, so after I switched powders, at some point it began leaking H335 into my RE-15! I decided to disassemble it, which I have never done before, and at least a full 5.56 charge of powder ended up falling out of it! I cleaned it all out and put it together, but now I've got at least 5 powder charges of Re-15 that are contaminated and unusable. Who knows how many charges I've thrown in the past have been contaminated with minute amounts of other powders. I'm gonna have to start disassembling my powder measure between powder types now. Thankfully, it only comes apart into 4 main components, at least. UPDATE: After cleaning it, it works like new. Other issues I had seen like increased friction and leaking totally vanished after cleaning. It's not hard to clean, either, so I figure I'll just start doing that now.