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Bigscot
10-13-2005, 10:53 PM
I have always been curious as to what method of measuring a powder charge produces the most consistent performance. Is it better to weigh a charge or use a volumetric device? I know professional bakers tend to use weight measures for consistent results because of the variance in moisture content of the ingredients but that is not an issue with gunpowder.

I have also heard that volumetric measures such as Lee's dippers work well. I use a powder dump then weigh the charge on a balance scale and trickle any additional powder as needed. Sometimes I wonder if the little amount of powder I may add to or remove from the charge really makes that much difference.

What does everyong else use and what are your thoughts on the two methods?

Bigscot

felix
10-13-2005, 11:14 PM
Bigscot, powder is energy. You measure energy, not volume or weight. But how do you do that? The theory is that once you get the group you are looking for, then set the measure up for that amount of energy, and that is by volume.....because the only difference in weight would be the water content of the powder. And, water does not contribute to energy. Well, I am not too sure of all of this theory. But, I do volume settings in BR work, but that is the only time. ... felix

drinks
10-13-2005, 11:24 PM
I have used the Lee dippers for nearly 40 years, first set was from Lee Engineering, long gone, It is now Lee Precision.
I have tried the dippers with a bunch of powders, with fine grain and ball powders, the accuracy is very, very good, with the long tubular powders it is only very good, that is ,better than any other powder measure I have tried.
Variations are on the order of .2gr +- with the large kernel powders and .1gr +- with the small grain and ball powders.
I do not believe the variation is important, variations between lots, seating depth, primer power, bullet diameters and the way you hold your mouth when you shoot are at least as important.

Blackwater
10-14-2005, 12:09 AM
Bigscot, there's a fly in the ointment when it comes to answering your question. Back in (I think it was) the 30's or so, Julian S. Hatcher wanted or was assigned the task of making US military match ammo more accurate. First thing he tried was weighing charges instead of using the automated machines to load the rounds. The irony was that he found the weighed charges LESS accurate on target! He repeated these tests a number of times, too, because the results seemed so contraindicated, and to make doubly sure his results would be accepted. He said he didn't know why this was, and the only potential explanation he could think of was that the dumped (volume measured) charges bulked up better, and thus had more air space in the powder column, and that this might have allowed the primer flash to penetrate the powder charge better, thus producing more uniform ignition. He did, however, say he wasn't wed to this theory, but I think what we know now probably supports his theory. Nobody's come up with a better explanation, that I know of.

The only way to find what's more/most accurate in any given gun is to shoot it using the ammo and specs, and let the targets tell you what the rifle wants. It's a lot like dealing with a woman, actually. [smilie=l:

StarMetal
10-14-2005, 12:13 AM
That doesn't hold water with ball powder, compressed loads, and longtude dropped loads.

Joe

David R
10-14-2005, 06:19 AM
That is a loaded question. It depends on the powder, the size of the charge, and the measure. 18 grains of SR4759 thrown makes bigger groups than weighed charges. 2400 makes no difference thrown or weighed. I think ball powders throw fine, extruded or flake powders could be either way. Like buckshot says, Let the gun tell you which it prefers.

David

Bret4207
10-14-2005, 07:37 AM
Consistancy is the issue. I have an old orange Lyman 55 set for 13.0 Red Dot. It works fine for that, but lousy with longer stick powders. My Redding BR measure works better with longer stick powders because it cuts them much easier adding to the consistancy. I've weighed charges from both measures and neither are any more consistant the me and a Lee dipper. That being said, I have a friend who couldn't use the dippers to save his life. 4-5 grain variations in larger dippers! He would double dip, shake, bump, not card the excess, a dozen different way to Sunday and no pattern to any of it. I think, for me and me alone, I can use any measuring system as long as I have enough time to figure out the pattern to using it consitantly. I PREFER to use a measure because I can go to a recorded setting and be close right off the bat. When trying new loads I often go with a Lee dipper if there's one real close to the charge I'm looking for rather than fooling with the measures settings. I check at least 5 charges on the scale in case Lee screwed up, never seen it yet but who knows?

Beau Cassidy
10-14-2005, 02:54 PM
When using a power measure, I throw 10 charges, take the average, and adjust from that. I feel it decreases my lot to lot variation. After shooting benchrest way back when, I don't get too hung up over exact charge weights.

Beau

mike in co
10-14-2005, 09:39 PM
yep a loaded question.....

the botom line is br, the most accurate discipline in shooting is almost exclusively thrown charges.
commercial match ammo is done by volume.
i'll bet black hills match is also volume.

mositure does affect results
br shooters will adjust thier best load for the days conditions.
have said all that....most of us can only afford convential powder measures....rcbs...etc..
and then there are beam measures that most of us can afford....5-10, 10-10's, lee perfect.
and dippers.....well its volume, but requires skill to be consistant.

the real question, what are you shooting and what is your definition of accuracy..

so define your desires, and see what tools will get you there.......

rhead
10-14-2005, 11:09 PM
I have tried controled test under controlled lab conditions changing both humidity and temp. In all cases with humidity the weight of a given charge of powder changed more than the volume. Flake powders changed the most and ball powders changed the least. A good scale will give the most reproducible weight butthat weight will not represent the same amount of energy. A good measure that is operated right will result in the most consistent charge. Also controling the conditions that the powder is exposed to,especially humidity, will help.

Scrounger
10-14-2005, 11:42 PM
I have tried controled test under controlled lab conditions changing both humidity and temp. In all cases with humidity the weight of a given charge of powder changed more than the volume. Flake powders changed the most and ball powders changed the least. A good scale will give the most reproducible weight butthat weight will not represent the same amount of energy. A good measure that is operated right will result in the most consistent charge. Also controling the conditions that the powder is exposed to,especially humidity, will help.

Forty years ago when I started reloading for shotguns, I read the same thing in the Lyman Shotshell Reloading Book. Basically that volume was more meaningful than weight. That is why I have to snicker when someone posts that the magic load is 31.3 grains. Neither they nor their guns could differentiate between 31 and 31.5 grains! Another well known gun writer wrote in an article that there was no need to get more exact than half grain amounts for loads under 30 grains and full grain differences for loads over 30 grains. I would add that for loads under 10 grains with the fast powders, then working in tenth grains might be justified. It's not Rocket Science...

Bigscot
10-16-2005, 10:18 PM
These replies are very intersting. I have always thrown and weighed charges for any accuracy/hunting work. For plinking I would throw, weigh, fine tune and then just throw remainders. But like I say, I have always been curious as to which method produced the most accurate results.
When adding to or removing from the thrown charges, I have wondered how much difference the few individual grains of powder actually made.

Bigscot

locutus
11-02-2005, 09:00 PM
Benchrest shooters shoot the most accurate groups. Most benchresters (all?) that I have known over the last 50 years swear by volumetric consistency, rather than weight. as some one said earlier, there is no energy in water.

An interesting experiment, and I don't know whether or not it's scientific, is to open a brand new can of powder, (smell the solvent?) weigh out 50 grains on your scale, let the powder sit out in the open in the scale pan for 48 hours, and then weigh it again.

You will be amazed at the change!

Personally, I have tried shooting groups with a couple of super accurate varmint rifles, and seen no difference whatsoever in group size between rounds dumped straight from the measure and those carefully hand-weighed.

Because of this, I load my 6MM Remington for a custom heavy barrel varminter on my Dillon 650. It still puts 10 (Yes TEN) rounds in 3/8 inch at 200 yards (Yes, 200)

Of course, these cases have had FULL bench rest prep B4 initial loading, and are neck sized only with Redding dies.