Lee Auto Drum Adjustment Trick

[buckeye43210]

Found this over on the Brian Enos Forums.

One cool thing is you can take a case and put it on a scale. Spoon in powder to the weight you want. Then grab a drum wind back the insert to give some room, dump the charge into the drum then wind the insert in till the powder is flush with the top. It's now basically 99% there. No need to muck around dropping and weighing heaps of charges.

[Ranch Dog]

Seems to me that the way to do it would be the way Lee has suggested for years. Start by determining the VMD of your powder and then apply the calculation to your charge. That works for me probably closer than 99% with my various measures.

The first thing I do when I crack open a new jug of powder is determine the actual VMD and I write it on the jug with a Sharpie pen. From there determining any setting is just math the way Mr. Lee had wanted these devices to be used.

Over the years I have figured out there is a slight variation in VMD, determined by the actual powder delivery system used. An example would be the Auto Disk used with a:

• a single disk
• double disk
• Adjustable Charge Bar
• Micro Disk.

The response of the powder filling the cavities are slightly different so I also note the device specific VMD as well as I try a different method of dropping the powder. An example of this is my recent addition of Trail Boss. So far I've only used it with three different measures"

• TRAIL BOSS (AD) VMD - .2271
• TRAIL BOSS (Dip) VMD - .2326
• TRAIL BOSS (PPM) VMD - .2910

Over the years, I've found this method to be exact from the start of the loading session. Knowing the specific VMD goes a long way to identifying any problems with your charges down the road and that is why I start with the math. If the math doesn't work out of the box, something is wrong with the setup.

[daboone]

Great post!
The minimal amount of time it take to obtain a VMD SAVES at lot of time monkeying around finding which disk or adjusting the micrometer setting.

[buckeye43210]

Ranch Dog, Using VMD gets a bit tricky as the Auto Drum doesn't have any calibration marks. You can count key turns. Each full turn of the key equates to 0.10cc and each flat of the 10 sided key equates to 0.01cc of volume change.

The Auto Drum instructions are as follows:

You can quickly preset the
approximate charge using
a Lee dipper or a weighed
charge. Then pour charge
into metering chamber.

Insert adjustment key
and rotate key until
powder is flush with
the face of the drum.

[Ranch Dog]

Okay, that explains it! Just save me more money as well as it is another new Lee product I won't be buying.

[daboone]

Ah come on RD it's not that difficult to count turns and then clicks to get it dialed in. The cost for the drums lends itself for a set 'em and forget 'em for a specific charge. As per the instructions you just weigh out the charge wait you want and then pour that charge into the metering chamber and dial the adjusting knob till the powder is flush with the surface. Easy breezey.

I must admit to collecting PMs. I have at least 9. Certainly don't use them all but I've spent a lot of time seeing what powders the dispense with consistent accuracy and ease of use. The Auto Drums and the Auto Disks are IMO best suited for a progressive press or turret presses. The advantage of the Auto Drum vs the Auto Disk is the infinite adjustment the Auto Drum is capable of. It is simply the PPM made for progressives or turrets. And the PPM is an outstanding performer for extruded/stick powders.

[buckeye43210]

My wife told me to order a Lee Auto Drum for Christmas. She's very understanding :-)

Has anyone tried moving the PPM drum to an Auto Drum body?

[akuser47]

Its sounds like to much work when reddings are so precise and easy to setup

[daboone]

The Redding is a good PM but it's not case activated like the Auto Disk or the Auto Drum. So it more work on a progressive or a turret.

[Ranch Dog]

Has anyone tried moving the PPM drum to an Auto Drum body?

Not a direct answer to your question but the PPM can be used on a Rifle Charging or Powder Through Expander die with the GunGuides Perfect Adapter & Sleeve if needed. Of course, it isn't die/press actuated & still must be manipulated by hand.

I epoxied mine into the funnel adapter end cap as I didn't want to worry about the stroke to charge the PPM, being you are pulling up, aiding in pulling the PPM out & off of the adapter. All my rifle shooting is at max loads so I want to verify each charge, also from the accuracy standpoint as well, so I don't use this setup as I don't directly charge the case until it is weighed.

I'm pondering all this for my use of the Auto Drum. Nothing to be gained in my operation other than possibly if I ever get a Load Master setup for the 7.62X39 & my Mini-30. Right now I have the powder deliver covered perfectly by the Pro Auto Double Disk using .82/1.18 cc cavities. This is a cast bullet load so that is delivering 42.0K PSI because of the alloy vs. the max chamber pressure of 45.0K PSI. I am still concerned with accuracy of the charge dropped but the Hodgdon Extreme powders are very Auto Disk friendly and drop with precision.