Making sure I am accurate with powder weight.

[gonoles_1980]

These are the steps I follow.

1. Make sure beam scale set to zero and calibrated.
2. Use calibration weights closest to the powder weight and check scale. Should be a few hairs off at most.
3. One my powder dispenser, use the VMD I have been documenting. If I have to make any major turns on the dispenser to set the correct volume to dispense the proper weight, then something is wrong.
4. Check horizontal, then vertical each case loaded with powder.

3 & 4 have helped me a few times.

Anyone else have any other checks that can be done?

 

[Reloadron]

Looks just fine to me.

Ron

 

[GLOOB]

I like your methodology. Just be sure to keep a log and label your ammo. Accountability is everything.

Here's an example:

The latest 45 load I made was slightly too light, leading to 2 or 3 short strokes. It was my first load with a new-to-me powder. Per my log, I used 4.85 gr Promo. This with a 200 gr cast bullet. Per my log, this load was noted to be a bit sooty, already.

I make sure to double check my load data, before simply upping the charge. I see 4.8-5.2 grains of Promo should be good to go.

Well, first off, I notice my scale is not calibrated right. It's weighing a tad heavy. It's been over a year since I loaded anything. A year and 1 week, per my log, to be exact. So I don't think anything of it. But I do suspect that perhaps my latest loads were lighter than I thought.

I pulled out the meter insert I used, as noted in my log, and dumped off some charges. 4.65 gr.

So I'm trying a new, stiffer load this time. Up from "4.85 gr" to 4.8 gr.

Today's log entry is an essay

 

[Hondo 60]

3. One my powder dispenser, use the VMD I have been documenting.

Would love to help, but I'm not making any sense of this.
Sorry, but #4 doesn't make any sense to me either.
IDK, maybe it's just me.

 

[GLOOB]

I dunno. Volumetric Display, maybe?

W/e it stands for, he means the setting on the meter. Rather than the actual weight as per noted on a scale.

I also trust the volumetric measurement more so than the scale. Unlike a scale that gets moved and recalibrated, a volumetric setting is more repeatable. This is why I stuck with dippers for so long. And now I use a dedicated metering insert specific for a given load. Once I have it dialed in, the scale is secondary.

 

[lauderdale]

What kind of scale/p.measure/check weights etc. and such do you use sir. ? Just wondering.

 

[Reloadron]

I dunno. Volumetric Display, maybe?

W/e it stands for, he means the setting on the meter. Rather than the actual weight as per noted on a scale.

I also trust the volumetric measurement more so than the scale. Unlike a scale that gets moved and recalibrated, a volumetric setting is more repeatable. This is why I stuck with dippers for so long. And now I use a dedicated metering insert specific for a given load. Once I have it dialed in, the scale is secondary.

I never liked the dippers and here is why. I used a 2.8CC dipper to run a simple test. I used IMR 4064 powder with the 2.8CC dipper. IMR 4064 has a volumetric density of 0.0745. So if we say VMD * Charge in Grains = Volume in CC we get 2.8 / 0.0745 = 37.58 grains or call it 37.6 grains. I used the dipper in two ways, skimmed and non-skimmed. Here is what I got and I stayed with the same technique with the dipper.

I weighed each charge and the scale was checked before use. I ran a total of ten charges skimmed and non-skimmed.

Here is what I got for numbers.



I found the dipper to have poor repeatability. That based on the above which anyone with a good scale, pencil and paper can do.

I use several volumetric powder throws including lee and my RCBS Uniflow and they both do much better than the dippers especially when a baffle is included in the powder hopper. Typically once setup I get within 0.1 grain on my throws and the better the powder throw the better the repeatability. Anyway, I never saw the dippers as very repeatable. Finally, the dippers will work better, in my experience, with ball or flake powders than for example the powder I used.

Even when I change loads I reset the micrometer on the throw and then weigh several charges before relying on the throw to be repeatable and even then I weigh about every tenth charge.

Ron

 

[GLOOB]

The reason I like volumetric measurement, even dippers, is for lot to lot consistency. This is all I care about with my pistol ammo, anyway.

For starters, I never leveled the dippers. I just do a heaping scoop.

While there may be a relatively large variability from one charge to the next, as long as the minimum and maximum charges are acceptable, I can repeat that with the next lot. Next year. Or a decade later. And I will have a high degree of confidence that this lot of ammo is the same as the lot I made last time. As mediocre or awesome as that last lot was, this one will be the same.

If I were to weigh every charge with an accurate scale, the variability might be much, much less. But one lot might be 0.1 grains heavier on average than the last lot. This may very well be the way I make rifle ammo. But I will never trust one lot to be exactly the same as another. Because of human error and drift in scale calibration.

Which is why I like dippers and powder throwers best for my pistol ammo. If I already shot 1000's of the same volumetric charge without a failure/jam, I am highly confident that it will work when I make more with the same process. Not to mention, I want the process to be fast and easy for pistol ammo.

Also years down the road, I can look in my log. And I know with which physical insert I made a batch of ammo. My log and these physical inserts are both integral parts of the system. No matter what scale I am using, maybe I even have a new scale. Maybe I dropped my scale. It doesn't matter. When I want to slightly increase or decrease that charge, I will compare the weight of the old insert with the new insert. So I will have a relative measurement - using the same scale, in the same sitting. I don't need to factor in calibration and the operator bias/error (which I'm the same guy, but years of time change my "eyes" and methodology).

You can say I was lax in my calibration. But a human error can't be completely ruled out of any situation that involves a human. I have already proven to myself that I can weigh the same thing twice and get two different answers. The physical insert, once locked down, is subject only to change through the laws of physics.

 

[Reloadron]

Actually, especially with handgun, as long as you get consistent and safe charges for a given volume I guess it really doesn't matter what the actual exact weight of the charge is.

Ron

 

[GLOOB]

Thanks for being open minded. Yes, indeed, that is my point. If my system produces 0.3 grains of spread with a chunky flake powder, I am perfectly ok with that as long as my guns function with that min and max charge. And as long as I get the same min and same max from one lot to the next. A "lot" being a reloading session... using the same lot of powder, obviously. My jug of Promo will probably last me over ten years, so that is going to be a constant.

 

[gillmeister692]

Please define "few hairs".

 

[Walkalong]

Today's log entry is an essay

I have had those.

I never leveled the dippers. I just do a heaping scoop.

I do the same thing, just scoop it the same each time, but no shaking or leveling.

 

[Rule3]

The "correct" way to use LEE dippers is to scoop, do not shake or tap, LEVEL with a straight edge like a business card. This will produce the most consistent "scoop"

Per Richard Lee the King of scooping

Your scooping may vary.

 

[gonoles_1980]

To answer some of the questions, I have the Lee Perfect Powder measure.

VMD = Volume Measured Density
I guess I really use CC's and not VMD, my spreadsheet converts back and forth. Every time I load, I note the CC's on the measuring arm, and document it. After a few loads, I use the average. My spreadsheet converts those numbers to VMD. (So why am I using VMD when I really us CC's)

Step 4. I put my blocks of loaded bullets next to each other, I use the flash light starting at the top left row, and move to the right, then to the next row etc. The flash light at the top left row, move down, then back to the next column and so on. That's what I mean. I have caught, an empty/double load that way, and have caught a "stuck" throw where one got a partial throw, the other got the full+partial.

 

[Lost Sheep]

4. Check horizontal, then vertical each case loaded with powder.

Thanks. That clears up a major question I had.
I read step 4 as you turning the case upside down (I was thinking you mis-used the word "horizontal) to guarantee there was no powder in it, then charging the case with powder.

Now I see that you were gang-checking the entire batch by horizontal rows and vertical rows.

These are the steps I follow.
3. One my powder dispenser, use the VMD I have been documenting. If I have to make any major turns on the dispenser to set the correct volume to dispense the proper weight, then something is wrong.

I assume you meant "On" rather than "One".

2. Use calibration weights closest to the powder weight and check scale. Should be a few hairs off at most.

I am confused by what you mean by "a few hairs".

Thanks for sharing your algorithm. We, as loaders are operating an ammunition factory (albeit a small one). We are our own quality control office, safety office and risk management office as well as the designers of the factory floor. We owe it to ourselves (and many others around us, too) to be as thorough in designing our "factory" and the operational algorithms and parameters as Remington, Hornady and Buffalo Bore, etc.

Lost Sheep

 

[gonoles_1980]

I'm thinking on the balance scale, being off by a few hairs would be a few 1/10ths of a grain. Unique has given me the worsts +/- .3. I have built a baffle, I'll see if that helps with the Unique.

 

[Blue68f100]

I'm thinking on the balance scale, being off by a few hairs would be a few 1/10ths of a grain. Unique has given me the worsts +/- .3. I have built a baffle, I'll see if that helps with the Unique.

Due to the large flake size of Unique it may help very little. I quit using Unique decades ago due to it's poor metering quality. Moved to Ball Powders and have not looked back. Running on a progressive you want a powder that meters accurately.

 

[noylj]

A bit OCD, but safe--and that is what matters.

>4. Check horizontal, then vertical each case loaded with powder.

What do you mean? Don't understand.
Are you talking about using your eyeball in LOOK in every case to be sure the powder height is roughly the same? If so, that is a really critical inspection.
PS: The beam scale I used in the early '70s moved very easily and I had to practically nail it down. I bought the very first affordable digital (electronic) scale that came out (late '70s). I still have it and it still works perfectly. Wouldn't own a beam unless electricity was no longer available.
So, be sure to verify the zero often, beam or electronic...

 

[thomas15]

Rule3
Posts: 4,464 The "correct" way to use LEE dippers is to scoop, do not shake or tap, LEVEL with a straight edge like a business card. This will produce the most consistent "scoop"

Per Richard Lee the King of scooping

Your scooping may vary

I wasn't sure that Richard Lee uses scoops to measure his powder. Nor was I certain he used a classic lee press so I googled "inside richard lee's reloading room" to see for myself.

The results were shocking...

 

[Dudedog]

VMD Volume measure denisity (?)
Grains*VMD=CC
CC/VMD=Grains
useful for Lee dippers or disk measures calibrated in CC