[MarkV]

When I use the auto disk to measure my bullseye powder it gives me an inaccurate measure every time compared to what it should be. It's supposed to be 6.4 grains and it's giving me 5.8 grains. I thought maybe I put it together wrong or something so I emptied all of the powder out and put accurate #7 powder in that uses the same index hole but is supposed to be 10.4 grains, and it puts out 10.4. I don't think there is anything else I could be doing wrong but obviously I'm doing something wrong. I just need some help figuring it out.

I only want to use this powder for some hallow points I want to make up. So I don't need to turn out a ton of these.

[The Bushmaster]

Bullseye is on the list of one of the hard to get correct drops. You need to add a trickler to your set up. I gave up on bulleseye when I found out that there were more modern powders that did the same job and measured better.:D

[Uncle Don]

This is from Lee's FAQ:

Powder cavity tolerances

The powder manufacturers allow themselves a 16% tolerance in the density of their powder, from lot to lot. We have to calibrate our chart to show the high side of that tolerance, so you should never get more than what the chart indicates, but you will sometimes get less. Believe the scale. If your measure consistently throws less than what the chart indicates, try going up to the next larger cavity. If the powder measure throws more than what the chart indicates, please let us know!

___________________________________________________________

Personally, I've never found a situation where the chart was dead on, close but not dead on. I usually go up one cavity from what the chart says and then weigh it before actually using it. That has served me well for years. I keep track of all my loading so it's easy to refer to the cavity I've actually used for a particular powder. Lastly, I haven't found that Bullseye one of the powders that have consistency problems, but then I've never had trouble with Unique either and that has been pegged as one for many types of measures.

[birddog]

I've had great luck with my Lee disks (I have 3 setups, for .45, .44mag and .357). But never ONCE does the Lee chart get it right. I rely on my scale, and weigh every 20th round or so once I get rolling.

Take the above advice, and rely on the scale.

[Rico567]

+1 on what "Uncle Don" said. Volumetric powder charging (a measure) is not a substitute for weighing (a scale). All published loading manuals list powder charges by weight, and for a reason, and it's the same reason that when you bake, and you want accuracy, you always weigh the flour. The reason is variation in volume. A good powder scale must be the guide to adjust the measure, or, in the fixed-cavity types, to select the proper cavity.
The published charts for any cavity-type measure (this would include not only the Lee Auto-Disk, but also such ones as the RCBS Little Dandy, and the "bushing" types, such as my MEC shotgun reloader) are strictly nominal, and usually those publishing the charts will say so somewhere in the fine print. Some powders, as has been mentioned, also just aren't as good at running through a measure. The big one, though, is changing lot numbers. If you're running close to the limits with one lot of powder, a 16% change can put you in the danger zone real fast. Never change lots of powder without weighing and recalibrating what you're dropping.

[DaveInFloweryBranchGA]

I agree a hundred percent with what everyone else has said about using a scale.

I own a Hornady Lock N Load measure that I have found to be more accurate than my Redding 3BR in practical accuracy over 100 rounds. Even with that accuracy, I ALWAYS weigh my charges and correct for any variational issues at the beginning of any reloading session with any powder. While most of the time the scale is dead nuts on, occasionally I've seen cases where I needed to tweak it, for whatever reason.

Based on what I've read on the forums, if you're measuring low and want to tweak your laods, I suggest you buy one of those Lee Charge bars to allow you to tweak your load to exactly what you wish. They're pretty inexpensive at Lockstock.com and should allow you to dial in your load to your satisfaction.

I hope this helps,

Dave

[Starter52]

+2. I find the Lee auto disk always weighs low with pistol powders. It's a kind of build-in "safety factor", I guess. I allow for this when I reload.

[The Bushmaster]

Barimetric pressure seems to have an effect on drop (gravity) cavity type measures too.

[JDGray]

I have had good luck with HS6 & Clays, in my Pro Auto Disk. I always fill the hopper to the top, and so far the disk has dropped the correct weight of powder. And after running my reloads over a chrony, I am happy with the consistancy.:)

[rbernie]

I've had great luck with my Lee disks (I have 3 setups, for .45, .44mag and .357). But never ONCE does the Lee chart get it right.That's a fact - the volumetric measurements are generall off, but at least they're off on the low side. However, I have never had an issue with charge CONSISTENCY, even with Bullseye and such.

[Starter52]

I agree with rbernie. My Lee autodisk may meter a bit lower than the chart, but it throws a consistant charge of powder each time. That's why I like it.

[The Bushmaster]

No argument here on the Lee Auto Disc powder dispencer. I have been using mine for around 18 years. I have modified or repaired it twice to keep it running. Mostly removing the clearence between the hopper and the disc to keep some powders from leaking out during operations. I would buy another one if this one goes beyond my ability to repair it.