I am using a Dillion 550B to load 115g 9mm with 5.5g of unique. I pick this combination for several reason.The biggest one is that it nearly fills the case and I can easily see the level and notice any deviation. I sit where I can see in each case just before I put the bullet on. Most of the time the powder measures correctly. But today after about a dozen or so loads, I noticed the powder level was very low. I
check ever thing for an obstruction and found none. I called the company for further advice. They only
ask me to check things I already checked. They were no help and even a bit rude. Their equipment will
not do that. I cleaned and reassemble ever thing and started reloading again. I had the same problem
after a couple dozen loads. So trust your equipment, does not work for me. Mechanical things fail.
Trust but verify!