I am going on three months of using the Lee Auto Drum powder measure and about 5,000 rounds loaded. It is a great measure and I have enjoyed using it. There are some undocumented features with this measure. One of them alerted me to an issue while loading 9mm Luger rounds. I'll explain a little later in this write up.
With any new piece of reloading hardware there is a period of time and experience needed to become confident in its function and repeatability. A trust factor.
Today I had a scare with my Auto Drum while loading 9mm Luger. My load is made up of xtreme plated round nose bullets of 124gr. Powder is 4.2 gr of Tite Group and Winchester small pistol primers. This is a combination I’ve loaded a number of times. I start my loading session by spraying the cases with lube. They were deprimed and cleaned before hand. I loaded them in the case collator of my Lee Load Master. The first case ran through the primer and the primer seated properly. I then weighed the primed and sized case and set the scale tare to zero with the empty case on the scale. I then charge the case with the Auto Drum. I pull the case from the progressive press and weigh it like I’ve done many times before. Perfect. 4.2 grain just like it’s dropped hundred of times before. I seated a bullet, check the overall and find it right where it should be. I check a few more times and then start loading a set of 200 rounds.
At 98 rounds I notice before placing the bullet that the case is short on powder. My first thought, did I some how rotate the hopper to off? The hopper still had plenty of powder in it. I ended up taking the unit apart convinced there was something wrong with it. There wasn't anything wrong. Everything was perfect. I found an added undocumented feature of the Lee Auto Drum. Somehow a 380acp case got mixed in with my 9mm. The 380acp case wasn't long enough to fully cycle the powder feed. This allowed me to identify the case wasn't right by not dumping powder.
This is the drums position during a powder dump into a case. The lower red mark shows the drum's full stroke.
If you plan to remove the dis-connector make sure to place the screw that is removed to take the dis-connector off is placed in the other hole shown in the manual. Some how I missed this and the dis-connector can still disengage if the screw is placed in the original hole.
When the 380acp case came under the charging die the rotation only rotated this far, not the full stroke. This kept the Auto Drum from dumping any powder into the 380acp case. I'm glad it is designed this way.
The Lee Auto Drum Powder Measure
This shows the drum position before charging a case. I put a couple of red marker on the housing to show the two normal extreme positions of the rotation.