Problem with Lee Pro Auto-Disk Powder Measure

[dsv424]

I have been using this powder measure on my Classic Turret for over a year now and it has always been pretty consistent within +/- .2 grains(even more accurate with powders like AA7) but lately I have been having trouble setting it up. I normally use it with adjustable charge bar for all my pistol loads. I realize that flake powders can be a problem getting a consistent throw. But yesterday I was setting it up for 5.6 grains of W231 which I normally set the charge bar at .64cc(I think, not in front of it now) to get this drop. Well I was getting drops of 2.5 g, 4.8g, 4.0g, even got one at .5g, although most were at the 5.6 range. Has anyone had problems like this and could it be an alignment or adjustment problem. Until I get this resolved I will have to measure each drop. Oh well.

 

[NuJudge]

The only problem I've had is when I don't concentrate on moving the press handle smoothly from the top end down to the bottom end, then back to the top end.

CDD

 

[RidgwayCO]

The only thing I can think of is you've accidentally placed the hopper on backwards. It will still work (sort of), but throws become very unreliable. Don't ask how I know this is possible...

 

[Noveldoc]

I have very good luck within 0.1 gr with the disc on pistol loads.

Tom

 

[Gadzooks Mike]

I haven't had any problems with mine, although I've only done maybe 600 or so pistol loads. I generally go slow and check every 7th or so on the scale, always right there. I have heard of folks getting a disk on backwards and it not working well and making me angry and.... ah.... no, I've HEARD of that, but I've not done it myself. Really. No operator error here folks. Move along.

 

[CU74]

I have heard of folks getting a disk on backwards and it not working well and making me angry and.... ah.... no, I've HEARD of that, but I've not done it myself. Really. No operator error here folks. Move along.

You're a good man, Mike. Fessing up to operator error, even underhandedly, is a true sign of a Great Merrycan. Congratulations.......

 

[jfh]

I'll vote for RidgewayCO's observation first. And--are the hopper screw-downs too tight?

And--if you have been leaving powder in the hopper, is a "clump" blocking the hopper bottom? The hopper is full, isn't it? Or, at least half full--

Then, other items to check:

1. Is the measure mounted with the proper drop tubes? Did you "change anything" recently, then remount the measure to a different PTED?

2. Watch the "F lever" action closely: is it running free? Is the slot in the measure base gummed up? Is the spring correctly connected? (see the Lee videos)

3. Are parts worn? Is the elastomer wiper jammed up on the hopper base? Is the disk / ACB worn so much that it can hang?

As much variation as you are reporting suggests that the disk/bar is NOT returning all the way to pick up a complete charge--and that kind of hangup tends to be caused primarily by the hopper being screwed down too tight. (For me, at least)

Jim H.

 

[dsv424]

Thx for the advise guys. I'll check some of those things when I get home tonight. I was at one time putting the hopper on backwards but that was a long time ago. I'm kinda leaning towards the hopper screws are to tight. I am constantly having trouble with that because you have to find a happy medium there. If its too loose then screws work themselves looser and if too tight then it hangs on you.

 

[jfh]

FWIW, My AutoDisk Measure--I have four--leak a bit with the AA Powders I use. Those powders are primarily #5, but with #7 and #9 as well. They leak less when I have new elastomer wipers installed, and they leak(ed) more when I had a well-used hopper (worn wiper) on top of a well-used ACB.

If you have been having no leakage with #7, then I would almost bet the hopper screws are too tight. Or, that the hopper / bar / wiper is somewhat worn, and you have kept leakage down by tightening the screws so much that the disk / bar is hanging up.

Jim H.

 

[dsv424]

Not sure if this is stated somewhere but how often should the wiper or other parts be replaced in this powder measure? In the first year I have made between 13,000 and 15,000 rounds with it. Or is it done when you think you might be experiencing problems.

 

[jfh]

re worn wiper, disk, hopper, etc.--

I've never actually measure the frequency for replacement--since my units are various upgrades over the years, it's hard to tell what was done when. However, as a WAG, I'll bet the wiper can go within 10K rounds--personally, I think mine went in less that. Overtightening the hopper nuts would, I think, exacerbate the wear.

Look for leakage across the top of the disk, as well as the (normal) leakage out the slot for the F lever. Leakage across the top will show the wear in the components; you can't, AFAICT, do anything about the leakage out of the slot for the F lever.

Look at the wiper first--then for any wear on the hopper bottom or disk/ACB top. Try troubleshooting the problem by removing the indexing bar and repeatedly actuating the powder dump with a case in place and using a stroke.

If the leakage source is not clear, then start by disassembling everything--including the PTED, riser, and swivel--and cleaning all parts. (I use GunScrubber / brake fluid on the die, riser, etc., and swab out the expander--use swabs, patches, etc. Disassemble the measure base, including the F lever retention spring and screw, clean the actuating lever slot, and so on--get it all clean. Then reassemble, put in powder--a full measure--and try locating the leakage again.

Personally, I am now betting on 1) worn wiper, followed by 2) worn disk /ACB, and that the problem is related to the hopper retainer nuts being too tight.

Keep us posted as to the results....

Jim H.

 

[Noveldoc]

And a handy hint for the dreaded screw threads in plastic. I got some Super Glue gel and rubbed a tiny amount into the threads. Let it soak in and dry, then carefully re threaded with my metal screws.

Much stronger and no wear now.

Tom

 

[dsv424]

Well thanks for everyones advise(especially jfh) I figured out my dilema kinda. I switched out the adjustable charge bar to one of my discs and I'm now getting throws within +/- .1 grain. Now I have to figure out why my charge bar is doing this? But at least I can now get accurate drops. I have the double disc set so I can fine tune the drops as well. Although I really liked the charge bar for quickly finding the correct amount of powder. Thanks again.

 

[jfh]

dsv424:

Since you've solved the basic problem (e.g., erratic drops, and now consistent ones), be rigorous in your problem solving.

Since your problem was with the ACB installed, try reinstalling it--and when you do, be sure you have it oriented correctly--i.e., that the F-lever is in the correct slot.

If you find no discernible wear on the components, that may well have been your problem.

Jim H.