Question about Lee auto disk powder measure

[forward observer]

Hi, I just got back into reloading after being away from it for 20 years. I pretty much had to start fresh since my old single stage press and dies were long gone. Consequently, I'm pretty much a noob again.

Anyway, I bought one of the Lee classic 4 hole turret press kits that comes with the auto disk powder measure, a small balance beam scale, and the Lee reloading book. A few days later, I also ordered a Lyman handbook and a digital scale, but was anxious to load a few rounds with what I had.

I started with 38 special, which I intend to shoot in a Uberti clone 1873 lever rifle--mainly for plinking and target. I had picked up some once loaded unprimed brass and 158 grn lead bullets at a gun show. The only applicable powder I could find locally was Unique.

The Lee charts in both the book and on die instruction sheet indicated a 4.1 grain starting charge of Unique for the bullet. It further indicated using the 4.3 cavity on the auto-disk. When I checked the charge on the little balance beam scale, I could never get the beam to hit the mark. It was consistant, but a bit low. This scale is not very user friendly if you know what I mean.

I finally guessed I might be a bit low on the charge, but was hesitant to use a cavity that had a higher charge volume than recommended. I went ahead and reloaded about 25 rounds and then stopped--thinking I'd wait until the Lyman book and the other scale arrived.

They arrived today, so I went to cross check things

It turns out that I was only getting 3.7 grains of powder from that disk setting--as weighed by the digital and cross checked with the balance beam scale.

To get to the min charge of 4.1 grains for Unique, I had to go all the way up to the 4.9 cavity on the Lee auto disk.

If you have taken the time to read all of this, here's my questions

1. Will it be OK to shoot the rounds I've loaded since they are only 0.4 grains under the minimum, which is about 10%

2. Is this a common issue with the Lee auto disk system, e.g., the charts listing the wrong cavities for the auto disk --at least for Unique powder anyway.

Thanks

 

[HisStigness]

1. I'm sure some people will come along and say it's ok, and others will say it's not.
2. The cavity size that Lee lists is just an estimate based upon the usual density of the powder. Richard Lee mentions that powder density can vary a bit between batches. Just try out some cavities and pick the one that's in a safe range (after a load work up to prove that said load is safe). If that doesn't float your boat, you can get the adjustable charge bar for your auto disk. Note: flake powders won't work in the adjustable charge bar if the volume is .4 cc or less.

 

[Gadawg88]

Welcome back to the addiction.

It might be safe to shoot the rounds you have loaded, but if it were me, I would pull them and start over as their performance will likely not be unacceptable. Why waste the components. Get a kinetic ( hammer type) bullet puller and you can re-use the bullets and powder as well as the primed cases.

I also use the auto disk for most pistol calibers I load. The chart in the instructions should be used as a suggested starting point to help narrow down which disk you need. The charge the disk actually throws should always be weighed and verified. Powder densities can vary from lot to lot accounting for some difference. I usually start with the next disk size up from what the chart recommends. Weigh multiple charges to be sure you get what you are looking for. Also be aware that certain powders meter better than others and give more consistent drops. I don't use Unique so I can't speak to that aspect. Also, consistent operation of the press is important if you want to get the most consistent throws. The rotation of the turret and bumping that occurs during the sizing and priming process can slightly alter the drop. This is not a problem as long as you are consistent. For example, if you just drop a charge and weigh it you might get 4.1 gn, but if you operate the press through a full cycle to load a round you may get 4.2 gn. Not a big difference, but something to be aware of when dialing in your load. Since your set-up is new, it may need a little breaking in before it settles down. You can use powdered graphite to rub on the disks and the seal where the hopper touches the top of the disk or just throw a bunch of charges and dump the powder back in the hopper.

Hope this helps.

 

[kcofohio]

Many of the recommendations for cc in Lee's handload book that I have used seem to err on the minus side. It could be because from lot to lot, powders can vary slightly on the density.

 

[Reloadron]

The Lee charts in both the book and on die instruction sheet indicated a 4.1 grain starting charge of Unique for the bullet. It further indicated using the 4.3 cavity on the auto-disk. When I checked the charge on the little balance beam scale, I could never get the beam to hit the mark. It was consistent, but a bit low. This scale is not very user friendly if you know what I mean.

38 SPL. Unique for 158 grain lead RN or SWC bullets. Min is 3.3 gr and Max is 4.2 gr.

Taken from the Hornady 9th edition.

38 SPL. Unique for 158 grain LRN and SWC bullets Min is 4.3 gr and Max is 4.7 gr.

Taken from the Speer 12th edition.

Those are handgun loadings not rifle.

We have countless threads in these forums with disparities in 38 SPL. load data. My best guess is they will shoot OK. That is my guess, the decision rest with you to shoot or not shoot these loads.

Ron

 

[rchery59]

I agree those loads might be ok to shoot. As far as the auto disc, what you have run into is normal. Be very careful with unique and small charges ,the auto disc does not like unique at all. It will have a tendency to drop inconsistant charges. You would be better off using universal or hp38/ w231 They meter very well with the auto disc.

 

[horsemen61]

I might shoot them out of a pistol maybe a short barreled model

 

[forward observer]

Thanks for all the input gents.

I should have mentioned that the bullets are lead flat point, which would be very similar to semi wad-cutter. This might make the Hornady data that Reloadron posted very close.

Nothing I've found distinguishes between rifle and pistol for the .357/38 with data for Unique. I would have preferred HP38/Win231, but there just isn't any to be found locally. I only got Unique because it was on the shelf and I knew that there was some load data for it at least in the Lee book.

Most info I have seen strictly looks at .357/38 special as a pistol caliber with some published data for the increase in muzzle velocity for rifle.

Then of course they have 44-40 (44WCF) listed as only a rifle round, even though today it's just as easily a pistol cartridge. Generally all the Winchester 73 chambering's were consider pistol cartridges anyway or at least they are today.

I purchased a kinetic bullet puller, but I guess I just don't relish using it for 25 rounds (actually 29). However, if everything is reusable, I guess I can live with it.

However, before I start, I may check some of the cowboy action sites to see if anybody has published any other info. I think this caliber is getting very popular with the CAS guys due to the low cost.

Cheers

 

[nevadabob]

forward observer...in your initial post, you mention a "4.3 cavity" and a "4.9 cavity". You mean 0.43 and 0.49 right? From my notes, I have listed that the 0.53 cavity will drop 4.1 grains of Unique.

 

[ArchAngelCD]

It turns out that I was only getting 3.7 grains of powder from that disk setting--as weighed by the digital and cross checked with the balance beam scale.

To get to the min charge of 4.1 grains for Unique, I had to go all the way up to the 4.9 cavity on the Lee auto disk.

If you have taken the time to read all of this, here's my questions

1. Will it be OK to shoot the rounds I've loaded since they are only 0.4 grains under the minimum, which is about 10%

2. Is this a common issue with the Lee auto disk system, e.g., the charts listing the wrong cavities for the auto disk --at least for Unique powder anyway.

Thanks

Welcome back to reloading...
You bought a very good press especially for handgun ammo loading.

My Lyman Cast Bullet Handbook lists a charge range for Unique in the .38 Special with a 158gr LSWC at 4.0gr to 4.5gr.

IMO thise 3.7gr loads will be fine but because they are using a lead bullet BUT I would probably not shoot them in a Carbine because of the barrel length. They might be fine but the long barrel concerns me a bit. If you have a revolver it would be better if you shoot them in a handgun instead. (but maybe not)

As for the Lee discs, like said above the chart is an estimation so be sure to weight the charges first when setting up. It's more normal than not to have to go one hole larger.

 

[forward observer]

forward observer...in your initial post, you mention a "4.3 cavity" and a "4.9 cavity". You mean 0.43 and 0.49 right? From my notes, I have listed that the 0.53 cavity will drop 4.1 grains of Unique.

You are correct. I was in a hurry and transposed what would normally be a cubic centimeter measurement in to grains. I found that confusing at first until I wrapped my head around the concept of the volumetric metering of the disk measure versus the weight measurement of the scales.

You are also right about the .53 setting. I had first tried .49 and then forgot that I moved it up another notch before I started hitting 4.1 grains consistently.

I've just used Excel to set up some of my own load charts so I can record
some of this for the future.

Somehow, I feel like I'm back in high school chemistry or physics again---only the equipment and text books aren't provided free of charge.

Cheers

 

[dickttx]

From the first few lines at the top of the PAD chart:

"This chart is a guide to determine the APPROXIMATE CAPACITY of all popular brands for each cavity. Actual charges may vary due to manufacturing tolerances
of the cavities, powder and method of use. These charges are not safe to use for maximum loads without first checking them on a scale. Most of these
loads are unusable for many cartridges. However, by not eliminating them at an arbitrary point, no mistaken inference of usable range could be concluded"

If you notice there are 24 disk holes and 84 different powders. That is a total of 2016 choices. It would be pretty amazing if they were all accurate! Not even taking into consideration different lots of the same powder.
The instructions for most measures say something like "Drop a load and weigh it, then adjust until you get what you want." Or, they have a graph, which really isn't any different.
You have a very nice outfit. It will serve you well.

 

[Rico567]

I used the Lee Auto Disk on two Pro1000s for over 15 years with complete satisfaction. But, as has been stated by several people in this thread, a measure of this design that happens to be accompanied by a chart of "probable" powder charges should never, EVER be relied upon for accurate weights. ALWAYS check with a scale.

It works exactly the same way with MEC shotgun reloaders and their bushing system. The MEC chart may say that a #34 bushing will throw 19.2 grains of Clays, but I sure wouldn't count on it. While it's less critical with shotguns, good, conservative reloading practice dictates the use of a scale there, as well.

 

[Wreck-n-Crew]

I too find the VDM charts off.

From my notes, I have listed that the 0.53 cavity will drop 4.1 grains of Unique.

And the Lee list is 4.9gr of Unique for a .53 disk cavity. I am using a .66 cavity to get 4.2-4.3gr Red Dot even though LEE VDM chart list's disk cavity .61 for 4.3gr. I get good consistent drops of 4.3gr, so I will stick with the .66 cavity.

Don't want to open up a can of worms on the weight vs. volume measuring debate but LEE says we are suppose to measure by volume. If they truly believe that, I wonder why they would not have any accuracy with their VDM charts? It's like having a scale that is off !:banghead:

 

[303load]

4.1-4.3. Typical lee drop. No problem just plinking. Good to use a digital. My old scale is where it belongs. In the box. My 38 setup exactly. Unique and all. Great versatile powder. Have fun.

 

[Tilos]

Throw 10 measures into a LARGE case and weigh it to get an average, rather than weighing a single charge.
This is way easier than chasing a single, varying charge.
Looking for 4.1---10 throws would weigh 41.0
Works with any powder measure

 

[Potatohead]

Out of the 40 or 50 times Ive used the disks, I dont think Ive ever hit a desired charge right on the head. You can tailor cavities to your own specs with a dremel or file, remember that it's permanent though.

Also you can pay 10$ for the little contraption with the the screw in micrometer dealy, whats the name of that thing? (I will find and edit)


Its called the Lee adjustable charge bar: http://leeprecision.com/powder-handling/powder-measure-accessories/

it works great if your charge is big enough and you have a decent throwing powder. Works well for me now.

 

[RandyP]

I made up a simple Word doc with the weight vs each hole size for my sole reloading powder Win 231/HP-38 and taped it to the wall of my reloading room over the bench.

It took a little while but for me it was worth the effort. I still verify the throw with my scale before each reloading session since I reload 5 calibers with the same powder measure and therefore switch disks.

 

[Potatohead]

That's a good idea. I look back at my notes to get a sense of where the starting point will probably be.

 

[Wreck-n-Crew]

Also you can pay 10$ for the little contraption with the the screw in micrometer dealy, whats the name of that thing? (I will find and edit)


Its called the Lee adjustable charge bar: http://leeprecision.com/powder-handl...e-accessories/

it works great if your charge is big enough and you have a decent throwing powder. Works well for me now.

I actually got one of those on the second Pro Auto-Disk that came with my press when I bought it (used).
Seems to work ok above 3gr. from what I gather, but it doesn't have the pull back lever (he lost it somewhere) so I just used the one without it for the moment. Think I'll give it a shot when I load for a different caliber and if I don't like it I can always use the regular disk.

 

[Dudedog]

I have found with some powders the caculated weight (Listed VMD and cavity size) are very close, other powders are off by quite a bit, and some powders vary more lot to lot than others.

The adjustable charge bar is ok but does not work well at small VMDs with powders of larger size. (flake) You can take a disk with an unused larger cavity and make it adjustable by drilling a hole in the side and using a machine screw. (thread on this here some place) I have also enlarged some cavitys to get what I want with one powder and just painted the top of the disk so I know I have done this. Yellow = w with x, green = y with z

 

[RealGun]

It probably doesn't take this many posts to simply share the rule to always use the next larger cavity than the chart indicates.

 

[BillB204]

I agree with the others that the auto disc is only a guide to get you close to the right disc. The estimate is generally low. So I normally start with one or two disc sizes higher. Then measure. Keep a good log of the throw weight for each disc cavity you try for each powder you try - even the cavities that you won't necessarily use for what you are then loading because you may be using that charge weight in that powder for a different load. It will save time.

I also agree that the charges you have loaded would likely be fine if shot in a pistol. But there is much more barrel for the bullet to clear in a carbine. A squib isn't the end of the world. But they sure are a PIA! I'd take them apart and get the right load.

I used a kinetic puller for years. And,because you have to smack it on a very hard (concrete or a steel plate) surface to get the most effective use out of the puller, I have broken more kinetic pullers than I kept track of. I would recommend a collet puller die. You'll spend a little more up front ($15-$20 for the die and $12 for each collet). But they will save you a lot of "exercise" in pulling the bullet and you won't have to buy a new one every hundred rounds. Here's how they work: Hornady Cam Lock Bullet Puller. You can get them at Midway: Press mounted bullet pullers. I have the Hornady system and am very pleased.

 

[Dudedog]

I have found some work out almost exactly as caculated. (Universal Clays)
VMD * GRAINs = cc.
Here is a spreadsheet to do some calcs for you to get a close estimate of disk size. It lists VMDs for a lot of powders. I have seen some powders vary from lot to lot and some the listed VMD does not seem close. (Unique)

Just using the next size disk without weighing charges could be dangerous IMO.
I always weigh about every 15 rounds once it is settled in. Sometimes more often depending on the powder.

 

[1SOW]

The LEE Disk system: Works very very consistantly with small ball & small rod powders.
Not as consistantly with larger flake powders, especially with light loads.
This can also be true with other powder systems.

The holes numbers are NOT the issue. The weight of the powder the hole drops is all that matters.
Weigh 10 drops and check the average. If THAT hole doesn't give enough powder, go to the next larger hole and repeat weighing 10 drops. When the powder weight falls in the load data range, it's okay to use.

If you need to have a drop "between" two holes, the holes can be slightly enlarged (from the bottom UP) and tested as it's being enlarged with very small changes in size at a time.. A disk is $5/$6 dollars each. One extra disk can provide a LOT of new holes. A slightly enlarged hole like "new hole 49.1" can add an extra .1 gr easily AND IT STILL WORKS PERFECTLY IN AGREEMENT WITH THE HOLE CHART. A Win-Win.