throwing small charges with a Lee Pro Auto-Disk

[xiang]

Hi all, first post here and though I am not casting just yet, I have been reloading for about a year on a Lee classic turret.

I have just ordered a revolver in .32mag and a handful of reloading components to experiment with the different cartridge options. Unfortunately, it seems that there is no easy way to use the Auto-Disk setup to throw small charges.

From what I can gather, the discontinued micro-disk was the best bet for this, but I have been unable to find one. I also got one of the adjustable charge bars, but it seems that these are not suitable for charges of less than 4gr or so without modification.

Has anyone been successful modifying disks or the charge bar for use with smaller calibers like the 32's? I really like the convenience of using this system and would rather not resort to dippers or an expensive powder dispenser if I can avoid it.

[Model29-2]

Xiang,
You are correct about the charge bar - no light loads are trustworthy when you get close to 4 gr. Have you tried the double disk kit from Lee? Look at the load volumes on the bottom of the page that comes with the powder measure. By combining different disks using the double disk arrangement you can fine tune the powder drop. (I am talking here about using the "pro" powder measure.)
I would stay away from any kind of flake powder with the disks and light loads. Keep with a ball powder (231, etc.) and they work OK.

[44Vaquero]

Unique, Bulleye, Blue Dot and Red Dot will all drop acceptable charges for the .32 Mag using the smallest Lee Disk. Do you have a Lee loading manual? If not I can scan the pages for you. PM me.

[xiang]

Currently all I have is Unique and 231. Bullets are Speer 98gr HBWC, and my Speer manual lists 2.0 and 2.4 gr of Unique as max loads for .32 long and .32 mag respectively. Will the smallest disk really drop such a small charge? I will give it a try later this week.

[44Vaquero]

One thing you need to remember about Lee disks is they are in-fact designed to throw a lighter charge then the chart shows (about 5 to 10% less in my experience)! The reason has do with the fact that powder manufactures can very the density of their product buy as much as 15%. Richard Lee designed the disks on the safe side with any starting load listed in his book should be under SAMMI specs.

I almost always end up moving up a cavity or two for my starting loads. Do you have a powder scale?

I used Hornady 90 gr HBWC's with 3.0 gr of Unique or 2.8 gr of Bullseye. You have to weigh the charges as neither of these loads is the cavity specified on the chart.

[fryboy]

a couple thoughts ( besides what's obvious or has been previously stated )
adjustable charge bar ... if you take one apart you'll note that the sliding bar is semi u shaped , by judiciously grinding away a small part of the two legs ( not the side the screw goes into ) you can make it a lil smaller ,
again for the adjustable charge bar ( but for bigger this time ) on the side the screw goes into there are two lil protrusions , these can be cut away to make it a wee bit bigger , and still a lil more is possible by shaving down more than just the two lil protrusions , dont want to go hog wild in either direction

lee disk ...

bigger is easiest - just waller it out ( common sense strongly applies btw ) drill it bigger or put a slight chamfer on it ( works best for a tenth or two )
smaller is doable but more intensive , best way is to plug a bigger hole ( epoxy and or a plastic plug ) and then drill out the desired ( but smaller ) hole - mark the cavity for future reference !!!
fine small adustments can be made by drilling and tapping the disk cavity on the side for a small set screw - screwing it in helps with fine tuning but i wouldnt recommend this for going bigger ( that common sense thing again ) a smaller screw the smaller adjustments , a larger one wont give as fine of results but allows for a bigger reduction

[xiang]

Thanks to all for the feedback. I have tried the smallest cavity on the autodisk with 231 and the throws are very inconsistent. I have not yet tried Unique. It looks like the small cavity isn't lining up with the hole very well, so maybe modifying a larger cavity will be more effective.

I've read that it's a good idea to run these HBWC bullets at low velocity to prevent deformation of the base, so I'm wary of throwing charges that are too high. My scale is pretty poor but it seems to measure OK within a few tenths of a grain. If I absolutely can't get consistency with the auto-disk setup, has anyone had good results with an inexpensive powder trickler for loads under 2gr? I wouldn't mind giving the 32 shorts a try.

[44Vaquero]

Ok, lets clear up a minor misconception: "it's a good idea to run these HBWC bullets at low velocity to prevent deformation of the base". That's what WC's are designed to do, bump up to engage the rifling! What you do not want to do is drive them so fast that they strip against the rifling or so much pressure that they blow out the end of the WC. 750 to 900 fps is usually were I strive to be with HBWC's.

Try turning the entire hopper around on the mounting plate, I think it changes it's position a small amount. YMMV.

I hope this helps.

[xiang]

Just wanted to say that I went with the Lee charge bar modification that involves using some material to close up the cavity a bit, allowing the opening to line up more evenly with the bottom of the powder hopper. I went with a trimmed piece of rubber eraser as mentioned on another forum. It seems to be reasonably effective and I am now able to consistently throw charges of 231 in the 1.8 gr range.