Lee Pro Auto-Disk Powder Measure-Does Yours Throw a Lighter Than Normal Load?

[gerrym526]

I've been using a Lee Classic Turret Press for about a year now with very good results. Bought the Pro Auto-Disk Powder Measure to use with the powder through expanding die.
Have noticed that there are times when I have to go up one number from the recommended powder/load in the chart because the number shown throws a lighter load. This has happened to me with both Bullseye and Blue Dot powders, so I don't think it's powder related.
Anyone else have the same experience using this Lee set-up? I usually check my powder load every 10th cartridge, and there are times when the load varies by 1-2gr (higher or lower than the charge shown in the chart that comes with the measure). I use a small but accurate electronic scale that I calibrate every so often-it's never been off.
Appreciate your comments on this-thanks.

 

[RandyP]

The Lee disks should be used after verifying with your scale what charge for YOUR powder the different hole sizes will dispense. I have found my Pro measure to be VERY consistent, but have actually never used the chart supplied with it that shows the various 'supposed' powder densities.

 

[Lost Sheep]

(edited for brevity)
...there are times when I have to go up one number from the recommended powder/load in the chart because the number shown throws a lighter load. This has happened to me with both Bullseye and Blue Dot powders, so I don't think it's powder related.
Anyone else have the same experience using this Lee set-up?
Appreciate your comments on this-thanks.

Almost everyone I have ever heard report on the Auto-disk.

Not really a fault of the Auto-Disk, but of the chart, or the operator. If you operate the press/measure with a lot of vibration you might be able to achieve the weights the chart indicates. For safety's sake the chart errs on the heavy side, making any charges thrown by gentler operators on the light side.

So, it is not really a fault of anyone or of the chart, but an imperative to all operators to do what is appropriate with any powder measure. Verify the weight dropped by your measure. Every time you set up and systematically throughout your loading run for statistical control. Lee powder measure or Belding & Mull, same rules apply.

If I found that any given Auto-disk cavity is showing a 1 or 2 grain variation, I would check my technique. Even if I had a 20 grain charge, a 5% to 10% weight variation would cause me to look for something off, either in the assembly of the measure or my technique.

What charge weight are you dropping that you are getting a 1 or 2 grain variation?

Lost Sheep

 

[1SOW]

First, I'm making the 'assumption' you're loading for handgun with the powders you mentioned.

Anyone else have the same experience using this Lee set-up? I usually check my powder load every 10th cartridge, and there are times when the load varies by 1-2gr

1-2 grains? or hopefully is that .1- .2 grains?

-I use the pro-disc powder system for 9mm. As RandyP said, it is VERY consistent and all drops are within .05 grs. or less with the several powders I use..
-Don't let the hopper run less than about 1/3 full.
-Make sure the hopper is 'completely' at the 'ON' position. If it backs off slightly It can affect the drop. The little screw underneath the hopper sets the tension for the shut-off
-When you first set up, it takes 4 or more complete cycles of the turret to get everything settled properly to be consistent. I cycle with handle all the way around the turret and then drop powder the into an old case with the spent primer still in and dump it back into the hopper. After several cycles the drop is boringly the same.

Every time you set the powder hopper to the "off" position and empty the powder below the shut-off, you have to go back through the 4-5 drop routine when you turn it back on. It can be as much as .2 grs off those first few drops.

-Make sure your handle pull is deliberate and goes all the way down.
-The drop does vary some from the chart with different powders, and being a little light is common. The finer particle powders, like 231-ball, Vihtavuori-small rod, AA-very fine ball, etc. tend to be a little closer to the volumetric chart numbers. The Win 231 4.4 gr hole might drop 4.3 grs, but it does so EVERY TIME, and that's what matters.
-Larger flake powders are the least consistent with the disc system because of it's trendency to "bridge" and form pockets in the disc hole.

The chart is useful when switching powders: It shows which hole to try first for the drop you select. From there you can increase or decrease as needed. Record the hole number for each powder that gives you the drop you choose.

Hope this makes sense and helps.

 

[16in50calNavalRifle]

Ditto to all the above. I have made my own chart as time has gone on, in which I have written down how much of a given powder (generally) is thrown by a given disk hole number. I use that as my starting point for the future loadings sessions, and typically have to go up or down one disk. Temperature and humidity affect the precise amount of powder each disk hole will throw at different times (aside from any mechanical issues such as consistency of reloader's handle pull, or cleaning/maintenance problems).

Well since it's a Pro Auto Disk thread, a slight hijacking. Just sat down after being flummoxed at the bench. Have not reloaded in several months, and when just setting up the press for some early morning Turkey Day reloading, I noticed the disk was not advancing forward over the drop hole as it should. It just gets to where it covers about 20% of the drop hole - this can't be right. I've taken the expander die/riser/powder measure assembly apart and reset and tightened it several times - no change.

It's 45ACP, using WSF. I've looked at the whole mechanism as I pull down the handle, looks good (as I remember it). But the disk is advancing far less than it should to cover the drop hole. Only thing I can imagine is that the piston (actuator?) in the riser or powder handler is not rising enough to move the disk forward properly, but how that could be has me puzzled. The FAQ on the Lee website has very spare info on this problem, and isn't really clear enough (to me) to advance the ball on this.

Any comments or insights welcome .....

 

[warnerwh]

You need to adjust the die in which cause more flare. It will force the disk farther out. Had the same thing happen to me and wondered why my charges varied so much. If there is another way to get that disk out further with less flare I'd like to know.

To the OP the disks typically throw less than the chart and you need to use a size or two larger. However with Universal I am finding the chart to be very close. The most important thing is to weigh your charges so you know exactly what you are throwing. Check charge weight at certain intervals during reloading to make sure all is staying put.

 

[tightgroup tiger]

-Make sure the hopper is 'completely' at the 'ON' position

Just to touch on something already said, I have to turn the hopper on mine completely past on, until it hits the stop or the dump hole only half lines up to the drop tube.
I know that's what 1SOW is stating but I wanted to explain why he said that.

I seriously hope you did mean .1-.2gr, but if you are get 1-2gr deviation take your drop tube assy apart and see if the actual drop tube is pushed the whole way in to the stop. Mine came through that way but it was only making up to .6gr deviation so I doubt that is the problem.

My pro auto disc also measures light with most powders so I have to go to the next larger hole to make weight.

 

[dragon813gt]

The chart is just a starting point. I've never had it throw exactly what's on the chart. I use Ranch Dogs VMD Calculator instead of the chart. Just google it. It's a spreadsheet that allows you to calculate the cc based on grains thrown. There is a section for calculating which autodisk to use.


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[wanderinwalker]

I don't think the discs have ever thrown the weight of powder charge the chart shows for a given powder for me. They are fixed cavity and very consistent for charging, but I do find it normal to step up to the next bigger opening to hit my desired charge weight.

The density of the powder will vary by operator technique and also lot-to-lot from the manufacturer. All of this will show as deviation from the chart when you check the weight of the charge. (And IMO the LEE chart errs to the heaviest lot/throw they've seen from a given powder, which would make sense from a safety standpoint if somebody isn't verifying with a scale.)

 

[gerrym526]

Guys-thanks for the responses-very helpful. And, sorry to panic some of you. I didn't include the decimal point (duH) when mentioning the variation of loads-it's .1-.2 variation, not a full grain.

 

[1SOW]

NavalRifle:

I noticed the disk was not advancing forward over the drop hole as it should. It just gets to where it covers about 20% of the drop hole - this can't be right. I've taken the expander die/riser/powder measure assembly apart and reset and tightened it several times - no change.

There is a spring tensioned actuator on the left side that is sort of "U" shaped. If there is too much play in the actuator it can cause the disc to not go completely forward.
Shim "some" of the play with a small folded piece of thin metal and the disc will move farther forward. It needs a "little" play to operate freely.

Just put a case in the shell holder and watch the actuator as you pull and release the case from the powder through die. You'll see what I mean.

Hope this helps

P.S. The square indexing rod is VERY sensitive to minute adjustments. Having the case dead center on the die helps smooth FULL actuation..

 

[dickttx]

16in50calNavalRifle,
Check to make sure the lever is in the correct notch in the disk. It should be directly under the disk size number.
Also, as warnerwh said, adjust the die in or out of the turret to center the disk hole over the drop hole.

 

[Hondo 60]

When I used the Lee Pro Measure, I NEVER found their data to be anywhere near accurate.

Back then I was reloading 4 calibers, with all sorts of bullets, to find the sweet spots in my guns.
And none of their disc data was accurate.

Please ALWAYS double check your powder throws on a scale.

 

[DanTheFarmer]

Hey 16",

I've run into this problem before. What was happening with me was that I was switching cartridges between cases of different lengths. A long case wouldn't allow the operating arm to go very far through its range of motion. Since the arm wasn't moving very far the disk that was full of powder wasn't moving fully over the drop hole leading to a varying, unpredictable, but undersized powder drop.

Try leaving the hopper off but putting the disk(s) on. Adjust the depth of the powder through die until the disk's holes are fully lined up with the drop hole when you cycle the operating arm. I found going from short (pistol) to long (rifle) to be the problem. If you are set up for a long case a short case will line up the holes with only a partial cycle which is o.k. by me...as long as I remember it's going to happen and don't try to force the arm to cycle further.

Good Luck,

Dan

 

[1KPerDay]

With any powder I've tried the Lee chart is pretty predictably optimistic by up to half a grain. I throw a bunch and weigh them and write the actual charge weight of that powder/orifice combination on the chart for future reference (always re-confirm with weighing charges when changing powders/loads/etc.)

 

[dickttx]

Quote from the top of the chart in the Lee instructions:

"This chart is a guide to determine the APPROXIMATE CAPACITY of all popular brands for each cavity. Actual charges may vary due to manufacturing tolerances
of the cavities, powder and method of use. These charges are not safe to use for maximum loads without first checking them on a scale. Most of these
loads are unusable for many cartridges. However, by not eliminating them at an arbitrary point, no mistaken inference of usable range could be concluded.
©"

 

[jim243]

The charts are approximations of what each type of powder will weigh.

ALL Lee equipment dispenses powder by volume not weight.

After all these years, I do not understand why people do not understand this.

Jim

If you want to despense by weight get one of these:

 

[dickttx]

I guess lots of people don't read the instructions, jim.
Don't know what kind of instructions the other companies have with their measures, but, I can't believe that "3.2" on the scale would be really accurate either. I do have an old, very expensive, Ohaus DuoMeasure that came with a graph. The Lee table is about 100 times easier to set up.
The instructions for the RCBS UniFlow say to dump a charge into the scale pan and weigh it, then adjust up or down. Seems like a lot more trouble than the Lee.
I have not opened the powder measure that came with my Hornady LnL AP, as I am using my Pro Auto Disk on it. However, the general instructions that came with the press do not say anything about a starting place.

 

[jim243]

Hi Dick,

All powder despensers, despense by volume, the exception is the electronic scale/despenser combination as shown in the photo (RCBS 1500).

Weight is not an accurate measure of how much powder to use. 5.6 grains of powder in my area 321 feet above sea level will not be the same as someone in Denver at 6,000 feet or Montana or Texas. But 5 cc of powder buy volume will be the same no matter where it is measured, density of water vapor or humidity will have an effect also.

So if I give a 5.6 grain load information to someone it is really just what will work where I live and loaded at the same time of year as I loaded it. For them it could be 5.8 grains of powder will give them the same volume that I use. That's why the disks will give you the same volume of powder each time but not neccessarly the same weight.

Jim

PS: open that powder measure up that you have been storing and try it.

 

[dickttx]

I only have a couple of thousand rounds thru my LnL. I decided to just use my Lee dies and PAD, along with an RCBS Lock-out die while learning. I also don't have to buy the powder die/expanders. At some point I probably will get out the Hornady, but I can't believe it is as easy to set up and change, or any more consistent than the PAD.