Ah yes, the infamous IMR4064. It can really be a heartache. I once hung up on the long grains and had to hit my handle so hard that the plastic cylindrical powder hopper flew right off the rest of the powder dispenser. The metal top of my powder measure landed on my Mitutoyo caliphers and smashed the glass in addition to the mess requiring over an hour to clean up. I learned half the cuss words I know while using that powder. Yet, I have rifles in 3 different calibers that thrive on IMR4064. I try to be more careful now, especially with where I place my calipher in case it happens again, and I'm sure it will, but I simply love the results I get from using 4064. It's terrific with medium capacity cases, so what's a guy to do? Best wishes.
Cal - Montreal