I had an interesting happening the other day...setting up to load some .38 Specials with Bullseye. Dillon measure. Filled it half way, and started to weigh the initial drops. 2.2/ something grains. Turned the screw head, threw some more. Stayed in the 2 to 2.5 range. Also the slide jumped and spilled powder when returning. Well shucks. Emptied the powder and removed the measure from the tool head. Measure seemed to work okay. Thought to remove the dispensing funnel. Stuck. Looked inside...packed with clumped hard powder. WTF. Scraped it all out and cleaned it up. Wondered how that could happen. Reassembled the measure and press and started over. Worked fine. FINALLY examined the clumped powder. OMG...the flake size is twice BE. Ding! Evidently my neighbor had been loading some .40 caliber stuff with another powder, had emptied the measure by pouring the powder out...but didn't empty the body of the measure by throwing charges until the body was empty. The residue had compacted into an almost solid mass over the month or so. I experimented with the measure...by just pouring out the powder without working the slide between 12 and 15 grains of powder was left in the measure. I learn something almost every time I reload.
Perhaps your measure had some residual stick powder left in it and somehow that got transferred to the main bottle of your 414.
I have no other explanation. Unless you do like I did once and had more than ONE can of powder on the workbench. Expensive fertilizer. Same neighbor had two cans on his bench. Loaded a large charge of Varget into his .25-06 instead of 4831. Cost him a new bolt plus new undies.
