Lee Pro Auto Disk modification

mjrodney · November 11, 2006, 09:16 AM

The Lee Pro Auto Disk powder measure has not been very consistant with Ordinary Clay's powder, so I made a modification to the unit so I can see potential squib loads with my own eyes, before I get to the range.

To test the mod, I loaded 50 rounds of .45ACP using a Lee Single Stage press and the modified Lee Pro Auto Disk.

I was able to visually see that the Disk failed to pick up a full load of powder 7 times out of 50.

Because I could see this failure before the powder dumped into the case, I was able to return the disk for more powder.

The attached photos show the modification.

FWIW, I will still continue to use my homemade powder dippers since there is no set up required. They are easy and accurate.

The modified Lee Pro Auto Disk powder measure is now my backup.

JDG · November 11, 2006, 02:24 PM

I use alot of clays in my 45, never had any problems(after the static cling problem) I coat everything with pencil lead, all the disk cavities, the rubber wiper, all the sliding surfaces. I also fill the hopper all the way. I've been impressed by the consistant loads. Sorry your having problems

amamnn · November 12, 2006, 02:41 AM

The main thing that the Lee pro system does not have that more consistent measures do, is a baffle. If you buy the baffle for the RCBS measure of reservoir similar design, and bend it open just a touch, you will be amazed at how much better it will work. Bridging will be prevented, and even flake powders will load much better. Also filling up the spaces where powder likes to hide inside the unit will help a lot. This can be done by running a tiny amopunt of ground mica through the measure.

swmike · November 12, 2006, 03:21 PM

I still use my old Auto Disk poder measure as it has the built in baffle. Will just convert to the "pull chain" system to prevent dbl charges.

benedict1 · November 12, 2006, 05:59 PM

Could you describe more fully the pencil lead treatment of the auto disk, bushng, etc that you noted above? I have had problems with Clays also and live in a very dry area and suspect static is an issue too.

For larger charges of flake powders like Unique, over about 4.2 gr, the charges thrown are boringly consisitent. Ball powders don't show enough deviation to weigh.

My only problem powder has been Clays.

amamnn · November 12, 2006, 06:08 PM

I'd like to see a Lee power measure of any type or age that has a baffle that was not added on later. Lee has maintained for years that their tapered drop tube eliminates powder bridging, which in the opinion of many, many users, it does not. Mica does the same thing as graphite, but without the mess and a lot more effectively than trying to apply graphite witrh a pencil.

JDG · November 13, 2006, 05:24 PM

benedict1,
I washed the hopper and discs with soap & water, let air dry, then sharpened up a pencil, for a nice long point, and simply coated what I could reach with it. (not the hopper) I coated all the cavities good, and sliding surfaces. My problem, when new, was Clays powder was getting behind the rubber wiper, between the rubber and hopper body. I couldnt get a consistant drop, to save my life. After the lead treatment things were better. HS6, is the best metering powder I use, and after running a bunch of that through it, my Clays problem went away all together. My powders are Clays, universal, power pistol, 231, HS6, and they all drop supprisinly close to what Lee list for the cavity.

Ausserordeutlich · November 13, 2006, 05:56 PM

Don't the adjustable charge bars work a lot better than the discs?

CrustyFN · November 13, 2006, 08:53 PM

I think it does until you try to measure to small of an amount. I tried to use less than 3 gr of Titegroup and had problems. I took the charge bar out to look at it and noticed it was just a narrow slit and the powder was having trouble dropping in. Other than that I haven't had any trouble with the charge bar.
Rusty

benedict1 · November 13, 2006, 11:56 PM

I have not had any good results with the adjustable bar and flake powders below about 4.5 gr. That narrow slit just doesn't work with flakes--either static or bridging or both give real inconsistency.

I have not yet found a situation, however, where an Auto Disk cavity doesn't get me pretty close to what I want; I am loading 3 different calibers of handgun ammo.

Wrangler5 · November 19, 2006, 04:20 PM

Quote:

I'd like to see a Lee power measure of any type or age that has a baffle that was not added on later.

The old style rectangular hoppers have a bridge over the hole going down to the measuring disk, that only lets in powder from the sides of the bridge. No direct connection between the downward pressure of the powder column above the bridge and the short powder column directly above the measuring hole in the disk. I believe the current Dillon measures have a similar bridge arrangement. These bridges serve the same purpose as the aluminum baffles in circular powder hoppers, that of keeping a consistent amount of powder above the measuring port regardless of the powder level in the hopper as a whole.

MADISON · November 19, 2006, 05:12 PM

The easiest way to solve that problem is with either an RCBS or HORNADY
"Powder Checker Die". All you need is another die space...

Ausserordeutlich · November 19, 2006, 05:43 PM

How does adding a powder check system "solve the problem" of inconsistent powder drops?

Here's a hint, regarding the adjustable charge bar: Yep, it probably won't accurately drop very small loads of some powders. When I was using a Lee setup, I never dropped really small loads of any powders. However, if you coat the charge bar with dry moly powder like one uses for moly-coating bullets, you'll see it "slick up" a lot. Also works for the Dillon charge bars.

Contrary to Lee, I also found it pretty simple to modify a charge bar for use double-stacked, with the Double Disk Kit.

mjrodney · November 20, 2006, 04:51 AM

Update to my original post.

Yesterday, I made up another 100 rounds with the modified Lee Pro Auto Disk.

Went to the range and I still had a noticible variance in power levels.

My Sig P220 wouldn't cycle completely a half dozen times and the case would hang up. My 1911 exhibited the same problem 3 or 4 times. Out of the 150 rounds, at least a dozen were noticeably under powered.

When I switched to a box of my reloads that were made without using the Lee Pro Auto Disk, all was well. Consistant, normal power loads.

I can only assume that either I have a defective Lee Pro Auto Disk

.......or Clays powder can bridge not only in the supply reservoir, but also in the Disk opening as well. The opening in the disk may appear full at the top, but in fact, there may be a pocket of open air below it.

No Mas.

XD-Guy · November 20, 2006, 02:09 PM

The lee charge bar works real good but its a Bear to get dialed in at first

benedict1 · November 20, 2006, 02:27 PM

It is not your Auto Disk, unless you have a faulty bushing coming out of the powder holder--check the edges of it to make sure it is not cut or rough.

I have tried Clays with an Pro Auto Disk, the Lee Charge bar and the charge bar in a Dillon SDB. From around 3.2 gr on down it just doesn't work at all. Either I get a charge, a light charge, or worse yet, nothing drops.

I believe it is a major static problem--I live in a real dry area. People I know who live in higher humidity environs don't seem to have a problem

Try the trick of wiping the powder measure, the disk itself and the part that holds everything with a clothers dryer fabric sheet, like Bounce or the ones from Costco; then with a rubber band, wrap it around part way on the powder measure, leaving a slot so you can see how much powder is still in the hopper.

If this doesn't work I would change powders, fast. Squibs are no fun. Go to a ball powder like Win 231 if there are loads for your weapon with it.

November 12, 2006, 02:41 AM	#3
amamnn Senior Member Join Date: May 13, 2006 Location: WA, the left armpit of the USA Posts: 1,323	The main thing that the Lee pro system does not have that more consistent measures do, is a baffle. If you buy the baffle for the RCBS measure of reservoir similar design, and bend it open just a touch, you will be amazed at how much better it will work. Bridging will be prevented, and even flake powders will load much better. Also filling up the spaces where powder likes to hide inside the unit will help a lot. This can be done by running a tiny amopunt of ground mica through the measure. __________________ "If the enemy is in range, so are you." - Infantry Journal

November 12, 2006, 03:21 PM	#4
swmike Senior Member Join Date: June 25, 2005 Location: Marysville, WA Posts: 670	I still use my old Auto Disk poder measure as it has the built in baffle. Will just convert to the "pull chain" system to prevent dbl charges. __________________ My definition of Gun Control--- A steady grip and hitting your target. "In God we trust, all others are suspects." "If I shoot all the ammo I am carrying, either I won't need any more, or more won't be of any help". ____________________________________________

November 12, 2006, 05:59 PM	#5
benedict1 Senior Member Join Date: July 26, 2006 Location: Southern California Posts: 245	JDG-Question re Static- Could you describe more fully the pencil lead treatment of the auto disk, bushng, etc that you noted above? I have had problems with Clays also and live in a very dry area and suspect static is an issue too. For larger charges of flake powders like Unique, over about 4.2 gr, the charges thrown are boringly consisitent. Ball powders don't show enough deviation to weigh. My only problem powder has been Clays.

November 12, 2006, 06:08 PM	#6
amamnn Senior Member Join Date: May 13, 2006 Location: WA, the left armpit of the USA Posts: 1,323	I'd like to see a Lee power measure of any type or age that has a baffle that was not added on later. Lee has maintained for years that their tapered drop tube eliminates powder bridging, which in the opinion of many, many users, it does not. Mica does the same thing as graphite, but without the mess and a lot more effectively than trying to apply graphite witrh a pencil. __________________ "If the enemy is in range, so are you." - Infantry Journal

November 13, 2006, 08:53 PM	#9
CrustyFN Senior Member Join Date: June 4, 2006 Location: West Virginia Posts: 2,258	I think it does until you try to measure to small of an amount. I tried to use less than 3 gr of Titegroup and had problems. I took the charge bar out to look at it and noticed it was just a narrow slit and the powder was having trouble dropping in. Other than that I haven't had any trouble with the charge bar. Rusty __________________ I don't ever remember being absent minded.

November 11, 2006, 02:24 PM	#2
JDG Senior Member Join Date: November 28, 2005 Location: West Michigan Posts: 673	I use alot of clays in my 45, never had any problems(after the static cling problem) I coat everything with pencil lead, all the disk cavities, the rubber wiper, all the sliding surfaces. I also fill the hopper all the way. I've been impressed by the consistant loads. Sorry your having problems

November 13, 2006, 05:24 PM	#7
JDG Senior Member Join Date: November 28, 2005 Location: West Michigan Posts: 673	benedict1, I washed the hopper and discs with soap & water, let air dry, then sharpened up a pencil, for a nice long point, and simply coated what I could reach with it. (not the hopper) I coated all the cavities good, and sliding surfaces. My problem, when new, was Clays powder was getting behind the rubber wiper, between the rubber and hopper body. I couldnt get a consistant drop, to save my life. After the lead treatment things were better. HS6, is the best metering powder I use, and after running a bunch of that through it, my Clays problem went away all together. My powders are Clays, universal, power pistol, 231, HS6, and they all drop supprisinly close to what Lee list for the cavity.

November 13, 2006, 05:56 PM	#8
Ausserordeutlich Junior member Join Date: May 27, 2006 Posts: 996	Don't the adjustable charge bars work a lot better than the discs?

November 13, 2006, 11:56 PM	#10
benedict1 Senior Member Join Date: July 26, 2006 Location: Southern California Posts: 245	I have not had any good results with the adjustable bar and flake powders below about 4.5 gr. That narrow slit just doesn't work with flakes--either static or bridging or both give real inconsistency. I have not yet found a situation, however, where an Auto Disk cavity doesn't get me pretty close to what I want; I am loading 3 different calibers of handgun ammo.

November 19, 2006, 05:12 PM	#12
MADISON Senior Member Join Date: January 1, 2000 Location: Roanoke, Virginia Posts: 2,678	not consistand powder charges The easiest way to solve that problem is with either an RCBS or HORNADY "Powder Checker Die". All you need is another die space...

November 19, 2006, 05:43 PM	#13
Ausserordeutlich Junior member Join Date: May 27, 2006 Posts: 996	How does adding a powder check system "solve the problem" of inconsistent powder drops? Here's a hint, regarding the adjustable charge bar: Yep, it probably won't accurately drop very small loads of some powders. When I was using a Lee setup, I never dropped really small loads of any powders. However, if you coat the charge bar with dry moly powder like one uses for moly-coating bullets, you'll see it "slick up" a lot. Also works for the Dillon charge bars. Contrary to Lee, I also found it pretty simple to modify a charge bar for use double-stacked, with the Double Disk Kit.

November 20, 2006, 04:51 AM	#14
mjrodney Senior Member Join Date: March 5, 2006 Location: SW Florida Posts: 435	Update to my original post. Yesterday, I made up another 100 rounds with the modified Lee Pro Auto Disk. Went to the range and I still had a noticible variance in power levels. My Sig P220 wouldn't cycle completely a half dozen times and the case would hang up. My 1911 exhibited the same problem 3 or 4 times. Out of the 150 rounds, at least a dozen were noticeably under powered. When I switched to a box of my reloads that were made without using the Lee Pro Auto Disk, all was well. Consistant, normal power loads. I can only assume that either I have a defective Lee Pro Auto Disk .......or Clays powder can bridge not only in the supply reservoir, but also in the Disk opening as well. The opening in the disk may appear full at the top, but in fact, there may be a pocket of open air below it. No Mas. __________________ Proud supporter of the NRA

November 20, 2006, 02:09 PM	#15
XD-Guy Senior Member Join Date: November 20, 2006 Posts: 102	The lee charge bar works real good but its a Bear to get dialed in at first

November 20, 2006, 02:27 PM	#16
benedict1 Senior Member Join Date: July 26, 2006 Location: Southern California Posts: 245	It is not your Auto Disk, unless you have a faulty bushing coming out of the powder holder--check the edges of it to make sure it is not cut or rough. I have tried Clays with an Pro Auto Disk, the Lee Charge bar and the charge bar in a Dillon SDB. From around 3.2 gr on down it just doesn't work at all. Either I get a charge, a light charge, or worse yet, nothing drops. I believe it is a major static problem--I live in a real dry area. People I know who live in higher humidity environs don't seem to have a problem Try the trick of wiping the powder measure, the disk itself and the part that holds everything with a clothers dryer fabric sheet, like Bounce or the ones from Costco; then with a rubber band, wrap it around part way on the powder measure, leaving a slot so you can see how much powder is still in the hopper. If this doesn't work I would change powders, fast. Squibs are no fun. Go to a ball powder like Win 231 if there are loads for your weapon with it.