Is the Lee Pro Auto Disk Chart way off for Unique?

[Lone_Gunman]

I was loading Unique for the first time yesterday, and the chart that comes with the Pro Auto Disk was way off for Unique. The dispenser metered Unique consistently, I just had to use a larger disk than was called for in the chart. I was trying to get about 5.6 grains, and the disk that was supposed to deliver that was giving about 1 grain less.

I have not had this problem with Win 231.

Has anyone else noticed this?

 

[trickyasafox]

i load unique with the pro disks too. i found i pretty much have to use the next size up to get the charge i want. YMMV but at least you know your not alone on this one

 

[MCgunner]

I've found the chart one or two discs off for a lot of powders. I weigh the charge to know for sure, only use the chart to get in the neiborhood of where I wanna be.

 

[bakert]

It's a bigger difference with some powders but the disks do throw lighter, especially with the larger ones, than shown on the chart for a couple of reasons. Powder can vary a bit from lot to lot, but I think the main reason is safety and CYA. I believe Lee claims they will not throw over what the charts show for that particular disk and ask to be notified if one does. I believe Lee reccomends checking with a scale to be sure, I know I sure do. There are many people who will just use a certain disk according to the chart with ever checking so it actually keeps some folks safer.

 

[Bula]

Another thing I've noticed about Unique and the Lee Disc measures, The same disc seems to throw different weights depending on humidity, temp, barometric pressure etc.. My 1.02 disc will consistently throw 8.4g on one day and 8.6 on another. My throw to throw deviation is sometimes zero for 15-20 measured throws.

 

[mparks]

Just used my Lee Pro disk last night. I've found that the 1.18 disc throws 9.8gr Unique and the 1.36 disc throws 10.8gr. I never look at the chart supplied. That is with my disk, my technique, and check on my scale so I'd throw out a huge disclaimer to just weigh and document what you get for each disk with each powder.

Another thing to watch that the chain is staying tight to pull reset the disk all the way. Mine got loose last night and I was throwing .2-.3 gr low for awhile.

 

[RobW]

I was loading Unique for the first time yesterday, and the chart that comes with the Pro Auto Disk was way off for Unique. The dispenser metered Unique consistently, I just had to use a larger disk than was called for in the chart. I was trying to get about 5.6 grains, and the disk that was supposed to deliver that was giving about 1 grain less.

I have not had this problem with Win 231.

Unique is a flake powder with a rough, porous surface that doesn't meter well in ANY powder measure. Win 231 is a ball powder that behaves like tiny slick glass balls and thus fills a cavity with the same density every time (my Lee pro auto disk throws less than ± 0.1 grain with W231 or TiteGroup.

I abandoned flake and extruded powders and just use ball or "short cut" extruded powders. I have only to check about every 25th case for accurate powder drop. Everything in the green range.

 

[benedict1]

I check the density of each lot of Unique--my last two were 19% light and 11% light; that is why every reloader using fixed cavity or preset adjustable bars needs a good powder scale--19% is a BIG variation!

In Southern California it is pretty dry and day-to-day fluctuation isn't too bad but my Auto Disk Pro can vary +-0.15 gr. I always check powder drop on Unique beforer every session for this reason. Whatever it throws on a given day because of temp./humidity variation it is very consistent +-0.05 gr from a Lee Auto Disk Pro.

With any flake powder DO NOT try to drop charges smaller than 4.0 gr--very inconsistent with any powder bar or disk.

W231 cavities are right on target with Lee data +-.05 grains. I have not used other ball powders.

 

[Stinger]

I get some wildly different numbers than you guys.

1.09 gets me 7.8, 1.18 gets 8.4, and 1.26 gets 8.8.

Stinger

 

[benedict1]

Stinger

Read my post above--what's the density of your lot of powder and is it real humid where you live? Your numbers aren't that wild.

 

[3rdpig]

I've found from the loads I've done so far that I'm usually two holes larger than what Lee says, and that's for loads around from 4 to 7 grains. It's hot and dry where I am, but my powder and reloading bench are in a house that's full time air conditioned, at least this time of year.

 

[benedict1]

Not unusual with Unique at all. Again, an accurate powder scale will tell you what to do.

Anybody have similar experience with Red Dot or Green Dot?