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The Shadow (Moderator)
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Discussion Starter · #1 ·
I get asked with some regularity, how I load by true volume when there is no data; So here is how I do it.

I use the Lee Perfect Powder measure. I looked at two others, but they only had hash marks and no volume references. Those others could likely be made to work, but didn't fit what "should be" in my head when seeking volume measurements.

So remember that the word REFERENCE does not at any point mean EQUALS. They are entirely different things.
Also remember that VOLUME and WEIGHT also are not the same thing.

If you open your favorite manual, and for your particular thing says:
START: 40gr. MAX: 50gr.
Then we need to get a VMD, or a REFERENCE point, to get from weight to volume.
So set your PPM to something close, because of trial and error I know that 3cc's will be close.
So measure out 3 CC's of that powder and weigh it; personally I take a 3 weight average.

Example: IF 3cc's weighs 42gr, then do some quick math.
3cc ÷ 42gr = 0.0714285 cc/gr. This is your REFERENCE VMD, for this bottle of powder ONLY.

Now you can take your Start and Max numbers, and calculate the CC approximation.
40gr * 0.0714285 = 2.857 CC
50GR * 0.0714285 = 3.571 CC

That is your reference, not your equivalent. Powder has a moving bulk density, kernel size, moisture content, etc. So if you decide you want to "check" your volume dispensed, you MUST check with another calibrated volume measurement device. Simply "checking" the weight, tells you nothing about the consistency of the volume being dispensed.

And as always, stay within pressure tested velocities; or understand you have exceeded the pressures tested in the data.

Hopefully that helps someone.

Cheers.
 
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That's a great way to do it. I calculate the reference "VMD" just the same way and ink it on the powder container for reference. The safety of the published VMDs by Lee is calculated by Lee, There is a safety factor from Lee to attend to powder lot variance. The Lee safety factor calculates to less than 2% by weight of the Lee VMDs in use. They work fine as is from Lee but checking is a reasonable caution too.

Personally, I will not measure by volume with loads hotter than 3% below MAXIMUM. When I go there, I use Lee scoops, a powder trickler and a balance scale for every charge. My old oil dampened Redding #1 balance is accurate to .1 gr and is the fastest dampening powder balance scale ever made bar none. So many people have these and hate them because they don't know oil goes in them for a dampening fluid. The oil dampening time is <1 second !!!! You won't beat that with anything.

https://www.google.com/imgres?imgurl=http%3A%2F%2Fthumbs4.picclick.com%2Fd%2Fl400%2Fpict%2F282149734503_%2FRedding-Model-1-Scale.jpg&imgrefurl=https%3A%2F%2Fwww.rimfirecentral.com%2Fforums%2Fshowthread.php%3Ft%3D776881%26page%3D2&docid=BdtixVoAAz0_IM&tbnid=iPdVuejj0DLknM%3A&vet=10ahUKEwjClIzvjJbeAhWsz4MKHejxDTcQMwg6KAEwAQ..i&w=400&h=300&safe=off&client=firefox-b-1&bih=654&biw=1366&q=oil%20damped%20redding%20%231&ved=0ahUKEwjClIzvjJbeAhWsz4MKHejxDTcQMwg6KAEwAQ&iact=mrc&uact=8http://

Gary
 

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There are two volumes to consider, too. It takes a dozen throws to 'settle' the powder over the hopper so that it weighs the same. That's a concern with progressive presses, but not when loading one at a time. Throw all charges then check by flashlight the levels in the case. You can see .2 grain in most powders if the case is 'full' with a full charge. (100% loading density.
I settle on a load that fills the case to the bottom of the neck. Weigh it and compare to what the books say and it's right there every time....and I weigh a few to be sure, but if the powder is slow enough, the case can't be over-charged.
 
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The Shadow (Moderator)
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Discussion Starter · #4 · (Edited)
Jack, this is about volume, not weight. Re-read the difference between REFERENCE and EQUALS
Loading by volume isn't trying to hit a weight.
If you use a volume device for achieving a weight that's fine, but has nothing to do with this thread.


Onondaga:
If you are using extruded powder, loading by volume is safer because of the burning rate control by geometry; not weight. Lots of folks get crazy if they cut extruded kernels, but it really doesn't affect the powder to any extent. Loading ball powder by volume can get you a foul of pressures more easily.

With as quickly as some companies silently swap suppliers, I personally wouldn't use someone else's calculated VMD. Strikes me as the same as looking in a book and pretending what was tested is identical to my lot of powder.
I did reference Superformance VMD's from Lee, and the number was substantially different than the lot I had. Which in pressure testing, was substantially different from what was tested in the Hornady manual. Another reason I'll test what is in my grubby mitts over talking someone else's word on what may have been at some time.

Cheers
 
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You can use volume all you want. It still go's back to what Jack has said, weighs the same.

Any measuring devise is set with a scale, the scale doesn't care if you use a powder measure or cut off
cartridge case's. All the scale does is measure the weight of powder in the pan,
in grains. That's what the rest of the world does to check powder charges.
 

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The Shadow (Moderator)
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Discussion Starter · #6 · (Edited)
The volume device isn't "set" with a scale, it's referenced to a scale, only IF you don't have load data in any other form. You are probably just to young to remember that finding volume load data wasn't all that difficult once.

And actually, NO; the world doesn't load by weight. The world loads by volume. That's why burning rate control in extruded powder was designed around geometry and volume. No one except reloaders use weight.
 

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The world loads by volume.
YES it does, but that volume is determined, controlled, measured and adjusted by weight, otherwise reloading manuals would not give weights, but would give volumes. We commonly use grains.
Scales are used to 'set' measures which are adjustable in volume.

The volume of powder used is determined by the size of the case and burning rate of the propellant, weight of the bullet and other factors, but it's safe to use the experience of others as published for nearly a hundred years to get close. THere is NO NEED to start at the #1 burning rate powder and determine each powder's safe load in your rifle. You can go to a book and pick a proper powder and start there. (Loads aren't found by the scientific method, though some try.)

The best accuracy and velocity is normally attained when the burning rate is proper to burn a whole case full of the proper propellant. THEN, when loaded by volume, it can't be overloaded and short thrown under-loads are easily seen.

My point is to assure consistent density when measuring, otherwise ACCURACY is variable, and that is more important than weight of the charge, but it's different too. That means we can determine density by weighing measured charges. SHaZam!!

Volume expressed as percentage of cartridge case fill means something to a reloader, but CCs don't unless you're giving injections. ;)
 
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The Shadow (Moderator)
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Discussion Starter · #8 · (Edited)
1) YES it does, but that volume is determined, controlled, measured and adjusted by weight, otherwise reloading manuals would not give weights, but would give volumes.

2) The volume of powder used is determined by the size of the case and burning rate of the propellant, weight of the bullet and other factors..

3) The best accuracy and velocity is normally attained when the burning rate is proper to burn a whole case full of the proper propellant. THEN, when loaded by volume, it can't be overloaded and short thrown under-loads are easily seen.

4) My point is to assure consistent density when measuring, otherwise ACCURACY is variable, and that is more important than weight of the charge, but it's different too. That means we can determine density by weighing measured charges. SHaZam!!

5) Volume expressed as percentage of cartridge case fill means something to a reloader, but CCs don't unless you're giving injections. ;)
Jack this is no different than the pressure thread, and you have the same amount of confusion here.

1) If you need 4 cups of whole wheat flour, do you determine what amount a cup is by a volume device, or a weight? Again, not the same thing.

Using the VHS argument, while cute, means nothing. "If VHS was technically less superior to betamax, we never would have used it":rolleyes:.
Volume data was regularly published widely, and currently still is by Lee. The point of this was to reference to volume, is you didn't have that data available to you.

2) Perhaps those who pressure test and develop load data, that has nothing to do with a reloader or this sticky

3) We are talking volume, and specifically CC's. "The best" velocity and accuracy is individual context dependant. You should know that highest velocity may or may not correspond with highest accuracy.
Your "fill the case with the 'right' powder and it can't be overloaded" is about pressure, which we aren't talking about. And since you can't measure pressure; is a foolish claim you seem to love to repeat. As is a blanket statement of short filling. You can't look in a case and see 0.1cc difference. That's no different than your claim made on one blurry photo of a primer where you magically came up with a specific firing pin protrusion measurement.

4) This is the same circular nonsense as in the pressure sticky. Density is a weight per volume. Extruded powder in particular, has a variable density BY DESIGN. Weight alone cannot tell you density, nor can volume alone.


5) 100% case fill of "my cases". Isn't a volume, it's any number of volumes. Unless every reloader measures each case, % case fill means at best, an arbitrary unknown. Weight means something of they have a scale. And if they have a volume measuring system, CC's mean something. People who have powder dispensers with only hash marks have a powder dispenser, not a volume measurer.
 

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"volume is determined, controlled, measured and adjusted by weight"
You almost got that right. We use the convenience of weighing (in grains) to ensure that the volume of powder we are using in a given load is correct. The weight serves no purpose, other than to verify the volume. Anyone who has worked with one or two wildcat cartridges learns this truism, one way or another.

Also, it is a bit absurd to assert that
"Loads aren't found by the scientific method..."
That is EXACTLY how published loads are found; by eliminating all variables, save for volume of powder, (expressed to reloaders by weight) to determine which combination of components will create safe, consistent and accurate loads.

For anyone who doesn't understand that VOLUME is what matters, consider the following exercise and the dire consequences from it. Put a charge of 4350 or 4831 (confirmed by weight) into a coffee grinder until it is a very fine powder, then load it in your 270 or 243. It's still the correct "weight", so it's perfectly safe, right? OF COURSE NOT! :eek:
 

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The Shadow (Moderator)
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Discussion Starter · #10 · (Edited)
For some fun about pretending looking at case fill tells you something, what does it tell you? Does it begin to explain individual kernel density? Does it speak to a volume dispensed?

2 Creedmoor cases fired in the same rifle with the same load. Both resized with the same dies on the same day, with the same press, and re-primed with the same sleeve of primers.

Dispensed and checked in a "Left, Right" manor each time.

Set the PPM to 3cc's and load it with CFE223.




I'll Grant I'm not going to win any photo awards:D but you can clearly see the car fill difference. So what is the weight difference?



The case that appeared to have less case fill, had more weight of powder in this instance. Now let's dump that out and switch to 3cc of Norma URP.




I'd personally say the left was very slightly less full, but almost sixes.





In this instance, we see the one that looked very slightly less filled, did in fact technically hold slightly less powder by weight.
No reasonable person would say out loud, that they could "see" the weight differences; and know what they were without weighing them.

A consistent volume of powder, will have a variable weight of powder; and further reason why loading ball powder by volume, can more easily get you into pressures you weren't expecting.

Again this was never to say that method A can beat up method B.
Simply how to calculate approximate load info for volume systems if all you have is weight. No load data should ever be taken as absolutely unchanging, and "guessing" your bottle of powder is identical to what was tested, is a fools errand. Much the same, thinking volume and weight are equal, is incorrect.
 

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The Hog Whisperer (Administrator)
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I read Darkker's (first) post as simply a good method to check the relative density of a particular lot of powder, such that it can be quickly 'translated' to CCs for those who prefer to charge by that method. And there is nothing wrong with that, as long as some allowance is made for the fact that powder WILL settle in the measure. Rapping the powder measure with your knuckles, and then throwing a few charges before you start, is probably a good a practice as any. That, or purchasing a baffle.

It should be well nigh impossible for ball/spherical powder to settle anywhere as much as stick powders, so if I had the example as shown in the photos (and both cases has been sized in an identical manner), I'd be dumping the powder out of those cases and checking the water capacity. Something isn't right. I've thrown a LOT of charges with ball powder, maybe checking every 50th one on the scale, and never seen the least bit of difference in perceived 'case fill'. Rifle/pistol, it just doesn't matter. Ball powder doesn't vary by a tenth of a grain in my powder measure. Set and forget.

As far as 'cutting' a few kernels of long-grain stick powder... it just isn't going to matter. Ever. Count how many are in a typical charge, and how many you just cut. Tiny fraction of a percent? Yes, there will be a couple of powder granules that will burn SLIGHTLY faster. But not enough to matter. Likewise, I used to get real wound up by a powder charge being off a tenth of a grain, till I pulled down some reasonably accurate factory ammo (due to crappy bullets) and got to weighing charges. All over the place - wish I had written down the range but over a grain for sure, maybe more. In a 50 grain charge, half a grain either way is only plus or a minus one percent. If that makes for a pressure excursion, you were already skating on thin ice. If it makes for poor accuracy, fiddle with the charge till get you get on an accuracy node. If you want to shoot competitively, then do what you need to do; invoke voodoo, make sacrifices, stare at the chronograph, etc., till the results on the target suit you.

The final burn rate & pressure curve for ALL powder is a function of both geometry, and deterrent coatings, but the scale tips one way or the other, pretty heavily, at times. Ball powder CANNOT be made to be anything but regressive burning, without a heavy deterrent coating, because the area of a sphere is proportional to the cube of the radius (I think; might be the square but I think it is the cube - will look it up later). Thus the amount of surface area burning drops drastically, very quickly, as it is consumed.

A flake powder with a relatively thin flake will burn nearly neutral, but is going to burn pretty quick in any instance. But it will be consumed in a relatively even fashion, because the large surface area of the flake is going to burn relatively constant, even if the diameter drops a teeny bit before the flake burns through. Put a lot of holes in the flake and it can burn relatively progressive, but not for very long, compared to a thicker stick or ball type granule.

A stick powder without any holes through it will be somewhat regressive, but not nearly so much as the ball, as the amount of surface drops as to the square of the radius (I think), plus a little on the ends, as the ends are consumed. Longer stick will be less regressive than a shorter stick. A stick with one hole in it should be, in theory, nearly neutral burning, as the hole in the middle gains area as the outer surface loses surface area. But I don't know if sporting powders really have a hole in them or not, and if they do, how fast the hole in the middle would ignite, compared to the outer surface. There are powders for artillery that are much larger 'chunks' that can have multiple holes through them, so that the powder is truly progressive, because there is more surface area being exposed as the powder is consumed.

The real advantage of making stick powders would seem to be that the deterrent could be mixed evenly throughout the powder, whereas with ball powders, they must have the deterrent coating applied more heavily on just the outside. I would imagine that makes the manufacturing process more complex, and a bit more 'twitchy' from lot to lot for ball powders? I am speculating regarding how the deterrents are applied to stick powders; it just seems to make sense to mix it evenly throughout the mixture, but maybe it is applied only on the outside? I don't know for sure. Anyway, even if deterrent is only on the outside of the stick powder, it shouldn't need as heavy a coating as a ball/spherical powder, to get the same burning rate. Maybe the powder manufacturers (for stick powders) would tell us how the deterrents are applied if asked; maybe not. It could be considered a trade secret, although I would think for stuff like the old IMR long stick powders, it would be pretty common knowledge by now. Anybody know?

With a stick powder that hits max pressure at around 100% of case fill, there is really nothing wrong with just making sure the case is full (once a load is worked up) and throwing the charges. But hey if trickling powder charges floats your boat, by all means - I used to do that, too.
 
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The Hog Whisperer (Administrator)
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Also thrown/swirled with H335. A bit less difference, but some difference, none-the-less. This can be useful when you really need a bit more powder in the case, and does show up on the chronograph as increased velocity from the increase in powder mass.
 

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The Hog Whisperer (Administrator)
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"Packing more powder in the case" isn't something that everyone has to do. If you have a cartridge were there are a bunch of suitable powders, then this doesn't really apply so much. But it can be a factor. It definitely is with the .35 Rem. Getting another grain or two in that cartridge can make a substantial difference in ballistics. It is a challenge to load for, because pressure levels aren't real high, nor is case capacity. Getting all the powder to burn consistently, at the velocity level desired, can take some 'fiddling.'
 

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Why in the world would you want to fill by volume in the first place? I have never seen data for despensing powder by volume other than that old Lee set of measure's! I do know how to make a measure to measure by volume, easy but it take's a scale as all data I've ever seen is in weight. If your wanting to load anything on a 308 case by volume, get a 30-06 case and fill with the chg you want in weight and then cut the case down so that the powder is at the top of the cut! Solder a wire handle on it and you have a volume powder measure. If the case is using stick powder, tap the side of the case and settle the powder in the case and trim. I can't see an advantage of any kind in doing that though. Keep in mind that the powder measure does throw powder by volume but you need to weight what it throws to know if it's safe with the data we have.

Oh, back up. I do set the powder measure with a scale for flake and ball powder then throw charges by volume. With the ball powder I check the weight every now and then to stay close. Stick powder won't measure that wel!
 

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The Hog Whisperer (Administrator)
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Why in the world would you want to fill by volume in the first place? I have never seen data for despensing powder by volume other than that old Lee set of measure's! I do know how to make a measure to measure by volume, easy but it take's a scale as all data I've ever seen is in weight. If your wanting to load anything on a 308 case by volume, get a 30-06 case and fill with the chg you want in weight and then cut the case down so that the powder is at the top of the cut! Solder a wire handle on it and you have a volume powder measure. If the case is using stick powder, tap the side of the case and settle the powder in the case and trim. I can't see an advantage of any kind in doing that though. Keep in mind that the powder measure does throw powder by volume but you need to weight what it throws to know if it's safe with the data we have.

Oh, back up. I do set the powder measure with a scale for flake and ball powder then throw charges by volume. With the ball powder I check the weight every now and then to stay close. Stick powder won't measure that wel!
Because it is substantially faster. That's why factories do it, and if you pull down any factory ammo loaded with long-stick powders, you may be appalled at the spread in charge weights. But, the factory stuff works well enough (usually). As careful handloaders, we may be horrified at the spread of charge weights in the factory stuff, but what it really tells us is that (usually) fiddling with powder charges to 0.1 grain spread is WAY, WAY down on the list of things that affect accuracy to any notable degree.

The bench rest crowd meters powder by volume, but they do so with powders that meter fairly consistently, and they are also under time constraints at a match to reload between relays. And doing it outdoors where it would likely be more aggravation than it is worth to try and use a scale. They have their loads worked up to hit an accuracy node, or at least be (reasonably) insensitive to plus or minus a tenth of a grain, or whatever their tolerance is. Mind you, they likely are using much better powder measures than our off-the-shelf stuff, no doubt use baffles, and basically have their technique down pretty well by then.

So metering by volume can be done and it can be done accurately enough for many purposes. I think that's what the point of Darkker's post is. You CAN do it - if you want to. Or you can trickle charges. Up to the individual.
 

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The Shadow (Moderator)
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Discussion Starter · #16 ·
Because it is substantially faster. As careful handloaders, we may be horrified at the spread of charge weights in the factory stuff, but what it really tells us is that (usually) fiddling with powder charges to 0.1 grain spread is WAY, WAY down on the list of things that affect accuracy to any notable degree.
.

So metering by volume can be done and it can be done accurately enough for many purposes. I think that's what the point of Darkker's post is. You CAN do it - if you want to. Or you can trickle charges. Up to the individual.
Precisely correct.

Do you like weighing? Then you should continue to do it and be happy.
Looking for a faster method that won't put you at a disadvantage accuracy wise? Then load by volume.
 
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