Lee Pro Auto Disk with Adjustable charge bar & 5.6 to 6.0 grs. HS6

[Case Stuffer]

So Lee warns that when using stick power with the adjustable power bar here may be bridging issues when set to 0.4cc or less. HS-6 is a very small spheral / flake power and I have loaded hundreds of 9mm ,125gr.Boolits with 5.6 to 5.8 gr of HS6 without any issues other than charges which vary from 5.4 to 6.0 which while not great were good enought for up close drills / practice with a 3" barrel striker fired concealed carry pistol.

Well last evening I saw that a case had a low charge in it ( i have LEDs mounted and do a visual) of every powder dropso I thew powder on scales and it was 4.5 grs. next charge was 3.7grs, so I emptied the measure checked the power opening in both the rearware where power fills the slot and at the from where it drops the charge. It turns out that the alignment at the rear leaves a lot to be desired I switched to th 0.43 fixed hole disk and threw around twenty charges which ran from 5.8 to 6.0 with most of them being 5.9 gr. I loaded 40 rounds checking every other oe and this same range was maintained. This was on a Lee Classic Turrent using the Auto Index and on press priming.

Back in the 80's I loaded hundreds of thousands of .38 Spl and .357 Mag rounds on a Star Progressive and a similiar number of 9mm and 45ACP on a CH Auto Master. I used WW-231 which is extremly close to same size and shap grains as HS-6. Both of these progressive presses used fixed hole size ,changeable charge bar inserts and they threw very consistent charges .

Note the adjustable charge bar does great throwing 24.0 grs. of H335 or even 18grs. of the same for cast Boolits I am trying in a AR15 M4.

[Litl Red 3991]

You said the magic word. FLAKE

And you've noticed the adjustable does great for large charges.

Most adjustables that screw adjust will screw up light charges of any powder that isn't truly spherical. My Dillon and Lee both have problems when they're at their smallest. It's the shape they make at the corners that gives problems with any powder other than ball shaped. The best possible cavity for the job is a round hole. No narrow corners.

The interior shape on the two sides is a wedge the powder has to fill uniformly. Flakes and sticks don't do that well at all. And flakes lie flat on the top of the slide as powder from the reservoir tries to flow down into the cavity. They don't have to bridge to obstruct the opening, but they'll do that at the corners.

Lee appears to have considered that. They warn against some powders uniformity problems. They also invented the disc's with their fixed (round) holes. Adjustables will always have a problem creating tiny cavities without corners.

Knowing about the problem is about the best we got. Not everybody wants to use spherical every time.

139314

[anhurset]

While I load some rifle calibers on my Lee Turret my main use for it is for handgun reloading (which is also likely what most people use it for given the vertical slack in the disk lockup which is prone to producing variable OAL in longer cartridges) and I've found the Micrometer bar utterly worthless for that task. I'm confused as to why they chose that shape for the cavity in the Micrometer bar, a circular opening at the lowest setting which would become a progressively longer ovoid/oblong shape as the charge increased would have negated the sharp corners and would likely have metered a wider array of powders better, especially at lower charges.

[Litl Red 3991]

I'm guessing that Lee chose that shape to get higher weight charges from the space available. Their disc set goes down to .30cc for the smallest hole. That's only about 5mm across. The slide only has 9mm of room to move in and out. They could make the slide over twice as wide by making the hole almost square at one end, about 12mm wide instead of 5mm. But then to get small amounts, they had to make each end almost square. The cavity would obviously be way too narrow then for anything but spherical, and small balls at that.

The Dillon measure I have has about the same cavity shape when screwed down. They both work for most people probably because there has never been a strong demand for ultra-light loads from the general public. The demand for target loads used to be by a population that fewer choices, didn't have such a high percentage of reloaders, and didn't have automation easily available. Reloading manuals still mostly reflect the fact that few people reloaded DOWN, that the demand was for the highest velocity from each powder listed. In fact, some of the first "cowboy" data was simply cut/paste of loads for lead bullets, showing the usual highest velocity possible for Do Not Exceed and 10% reduced for Start Loads. Even Lyman's latest Cast Bullet Handbook for example shows Schofield loads based on max pressure for high velocity and 10% reduced for Start Loads. Schofield wouldn't be in load books today if it wasn't for CAS, yet the industry for the most part still doesn't get how it's being used. Cavity shape seems to be based more on heavier loads than lighter ones.

Lee used to offer a couple of different light load bars/discs once upon a time. Apparently their either wasn't enough demand to keep them on the market, or there could have possibly have been some kind of problem with marketing them.

[dragon813gt]

Lee used to offer a couple of different light load bars/discs once upon a time. Apparently their either wasn't enough demand to keep them on the market, or there could have possibly have been some kind of problem with marketing them.

None of that was the problem. The problem is their mold broke. I'm assuming due to the cost of a replacement and how few they sold in relation to the larger discs they decided to just drop the product.

The good news is that you can still buy the MicroDisk. An enterprising fellow decided to copy his original set. You can also order blank discs that you drill out to your specs.

But all this may be meaningless when they release the case activated auto drum powder measure.