Wobbly,
You are an amazing individual sir. I truly appreciate your desire to help and willingness to go the distance.
I was going to send you a PM over on CZ, and was actually trying to solve a very annoying problem with one of my AR15's, and while searching for an answer (like I always do before I post a question) I just happened across this post !!!
I am the friend Wobbly is referring to, and here is what I have to report:
I installed the powder baffle sold by UniqueTek and loaded some VV N320 into the hopper. It took me nearly 60 (yes I counted them) pulls to get the powder measure to settle down @ 4.1 gr. and only deviate by .1 grains according to the Dillon electronic scale.
At that point I decided to load some rounds and check for consistency.
I loaded 30 rounds, then weighed a few drops. It never went below 3.9 grains and it went as high as 4.2 when I took a freshly sized, primed case that I used to zero the scale. I dropped, measured and dumped that case another 10 times and as long as I kept the tempo consistent it would settle down right at 4.1 grains, but if I walked away to the other bench and came back and repeated the process, it took at least 5 or 6 drops to settle back down to 4.1 grains.
This is very odd compared to my experience with the other powders Wobbly mentioned I have have perfect success with (WSF and 231).
I may try to polish the innards of the powder funnel area and see if that gives me more consistent drops with N320, but so far I am not happy with the consistency at all.
I loaded a total of 100 rounds and I am confident that my peak is at or below 4.2 grains, but I do not have much hope that this batch of 9mm is going to provide groups that are worth writing home about knowing they (probably) vary by as much as .4 grains.
If I cannot get N320 to drop closer to .1 grain variances, then I will throw in the towel on it for a while until I feel like spending the time to see if I can improve the system by polishing things up a bit.
I will also call Dillon and see what they have to say as Wobbly suggests and see if they have any suggestions.
Mr. Wobbly, again I salute you sir. You truly are an asset to these communities my friend. Thank you for trying to help!