Lee pro auto-disc question

[actionflies]

Is it normal for my Lee pro auto-disc to be off by .1 or .2 grain? For example, I'm using Titegroup powder with 3.4 disc (4.0grn) and I'm getting 3.8grn. This is also the case with Win231 powder.

 

[wally]

The tables of charge weight vs. disk volume are only approximate and will sometimes change a bit with different powder lots. That's why you need a scale, period. If the new lot throws a bit lighter I ignore it. If heavier, as long as its still below the maximums listed in a couple of manuals I'll also just go with it.

Lee makes an adjustable measure you can tweak if you like, didn't work well for me with volumes below disk 0.44 and Unique powder when I tried .380 loads where splitting the difference between the two volume options would have been ideal.

--wally.

 

[Zippy06]

Yes.
Wally has got it.
On rifle cases, it might be 2 holes away. to get the correct weight.

 

[FieroCDSP]

For flake powders, I give the base of the hopper two medium-hard taps before dispensing. this helps the contents settle into the cavity, filling it more consistantly. If I don't, I get one right charge, two weak, a virtual squib, and then another weak. Wash, repeat, rinse.

 

[creekwalker]

Good post by Wally, right on the money. You’ll also find that with the Lee Pro Auto Disc or earlier auto disc as well as the Lee Perfect Powder measure that a little prep work is needed. In essence these very underrated and maligned powder measures should have a hopper full of powder run through them thoroughly coating the interior bearing and flow surfaces with the graphite residue carried in the powder. This is also beneficial in other powder measures before you start loading with them. Nothing new here as I’ve read this same information in other forums and Lee specifically recommends it. Surprisingly enough it actually works and I wish I’d know about it years ago when I first used an auto disc on a Lee pro 1000.

creekwalker

 

[RustyFN]

Yes that is normal. You always want to check with a scale to make sure it is throwing what you want it to and adjust if needed. I use a lot of Titegroup and find it to be very consistent with the Pro Auto Disk Measure.
Rusty

 

[subierex]

Yes, normal. I had to go the next bigger hole size when loading my last batch of 45 Colt using Titegroup.

 

[benedict1]

For flake powders, I give the base of the hopper two medium-hard taps before dispensing. this helps the contents settle into the cavity, filling it more consistantly. If I don't, I get one right charge, two weak, a virtual squib, and then another weak. Wash, repeat, rinse.
__________________

Get an RCBS Powder Baffle from Midway, Cabela's, Graf, etc. Cost about $7. Put it in your Lee measure. I can load anything down to about 4.0 gr of Unique with ±0.1 accuracy. For my 9mm 124 gr. RN plated loads I use 4.7 gr. Unique and see no variation whatsoever in weighed charges since I put the baffle in.

It also works great with Green Dot and Clays. Clays is even more forgiving--I load 3.1 gr. for some light .38 Special loads with 158 gr. bullet and see less than ±0.1 gr with it.