Lee Auto-Drum Powder Measure and CFE Pistol powder metering

Been experimenting and swapped from W231 to CFE Pistol, metering W231 charges in any of Lee Auto-Drum has always been consistent in the 5.1 gr (or plus range).

The CFE Pistol is a bit finer and my 38 spl loads really like approx 6.1 gr behind a 130gr LHP bullet at approx 950 fps (to meet power factor).  The problem is powder is dropping from 5.9 to 6.2 in any of the Auto-Drum measures.

Any suggestions?

On another note: 

I have (2) LEE powder drop dies marked 38/357 and (1) marked 38 spl, wondering if using the 38 spl die is better suited for the shorter 38 case while dropping powder?

Thanks

I've experimented with couple drum-type PMs (Hornady & Mark 7), and came to conclusion that accuracy of powder drop is greatly affected by cadence of loading.  In my testing 3-4 seconds was necessary to empty drum consistently, especially with fine grain powders (i.e. N310).  I believe, it has to do with powder flow pattern especially taking to account that drum is angled as opposed to being vertical when powder is being dispensed into the cases.  I also found that light tapping on handle at both drum filling up and emptying it positions help with consistency of charges.  I've never tried Lee Auto-Drum PM, but think it is not much different from ones I tried.

AP

Thanks...you got me thinking..maybe I could make a built in "knocker" of some type.  In the meantime I'll try tapping the measure to see if it makes a difference.


Just had a thought about static electricity playing a factor?

Just found this article:

https://bulletin.accurateshooter.com/2012/11/reloading-tip-eliminate-static-cling-in-powder-measures/

I've done a fair amount of tuning with the Lee AutoDrum but with VV N310. It's at least as consistent as my tuned Dillon DMs, but as PhotoEscape mentions it is sensitive to things including cadence.

I did not need to do grounding straps or vibrators to get consistently under a 0.1gr spread with VV N310. That's individually measuring each charge in 20 unit samples on a Redding T7 with a 0.02gr balance. CFE may vary.

I tried lots of things but suspect the following two were most impactful: (assuming case activation)
- make sure to not run the ram fast enough that the drum spins faster than your eye can track. I can cycle the Dillon faster than the Lee.
-make sure the unit is being fully activated. I used two Lee extenders to raise up the PM to clear the adjacent dies on my turret head. Both the PM and those extenders have rubber o-rings. Finger tight did not pull the assembly close enough to the die and sleeve to achieve a Full throw on the PM. Fully tightening the connections and especially the knurled nut on the bottom of the PM (not that easy to do, finger work) got mine to full (or close) travel. If those aren't fully tight, I had to excessively flare the case to get enough movement.

Other tweaks:
-Powder hopper baffle
-Pyrex powder hopper (dramworx includes the baffle)
-Not tightening the drum any more than necessary (if it isn't leaking, don't tightening. I can easily tighten mine further with my fingers but don't)
-Expanding with my Redding expander before the lee powder through die

Thanks all for the feedback...I'm beginning to think it's static related.  My workbench is solid steel (also serves as a welding table).  I only started "Noticed" having the situation recently after switching powders (W231 to CFE Pistol).

From what I read static electricity (SE) is more prevalent as Winter sets in.  Also read where the guys like how freely/nicely CFE Pistol drops via powder measures.

Learned that SE will affect the readings of electronic powder scales - which I use.

I'll get some static wipes and ground wire my Lee press and workbench...worth a try.

FYI: Just grounded my Lee 4000 press, metal work bench and wiped my digital scale down with an anti-static wipe.  Appears to be dropping the CFE Pistol 100% better...no deviations with drop weights.

Noticed that I no longer have powder clinging inside the clear powder measure bottle either.