weighing VS throwing powder

Not just when cold

FBecigneul said:
"It is my opinion that the "best" BR powders of the past and present are those powders which METER best."

I respectully disagree. Spherical powders meter best or near best and yet in cold and humid conditions shoot poorly in a 6mmPPC and 220Russian.
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Not just when cold or humid. I haven't had a PPC barrel that would shoot with any ball powder irrespective of what the climate was like. In fact in the last few years I haven't seen ball powder at a match. I would rather have a powder that shot well irrespective f how it metered.
Andy.
 
and we have abother winner...bingo to the man in wa

beating the dead horse go look at oem 8208.......

mike in co

alinwa said:
Interestingly enough, I always assumed spherical (ball) powder metered best........ until I had opportunity to load up several hundred rounds using 6 different ball powders.

Turns out I was wrong. IME it doesn't meter as well as "square" extruded powder.

I hope someone else takes the time to test this,
al
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alinwa said:
Well, no......I can keep ES (SD is a hoax, a crutch for number cruncher) under 10fps all the way through a "ladder test" (altho I don't DO ladder testing, I graph for a sine wave) and through a wide range of other variables. This happens to be the crux of my post. But it keeps getting obscured by guessers.

AGAIN it's obvious from most of the answers here that few of the respondants have actually DONE any testing like this.

:)

BTW a Chargemaster is no more precise than a powder thrower...... but to be able to say this, one must have actually TESTED instead of surmised.... Pete Wass is of course an exception here, since he is actually using the Chargemaster as it's intended, within it's parameters, as a rough THROWER.

I'm beggin' here guys.... TEST HIS STUFF!..... At least before opining out here in front of God and everybody...it gets really old hearing "I know this guys a nutjob because you an' I BOTH know that Cheerios are better than Cornflakes!! And Waltrip drove the TIDE car!"

;)

al
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Al, buddy,I think you've got to be kidding us again. I know some folks get their kicks from stirring the turds into the punchbowl, but sheesh, it gets to a point where it eventually drops the stock values of the stirrer!
 
Al,
Although I prefer to keep track of ES for this application, believe it or not, statistics was not invented solely for characterizing velocity data, and for many of the other applications, Standard Deviation is a useful tool, as a measure of central tendency. Of course you probably already knew that.
 
I suspect both Al and Boyd know that a good Standard Deviation number is actually more useful than Extreme Spread. The problem lies with "good." The statisticians tell us it takes at least 70 shots to have a reliable, comfortable number. Most of us use 5 or 10 shots and think we then have S.D. for a load.

That's where Al is right -- S.D. derived from a sample of 5 or 10 is useless.
 
The good Dr (yeah, that would be PhD) Oehler knows the value of SD. I don't usually get too concerned about letters after the name, but in this case, I'd take a P and and h and a D over a I and an N and a WA. ;):) Sorry Al.:eek:

But I don't see what all the fighting's about. ES and SD go hand in hand. You CANNOT have one good with the other bad. THey are either BOTH bad or BOTH good! Seems anybody that's been around a gun and a chrono and paid attention would know that!
 
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But I don't see what all the fighting's about. ES and SD go hand in hand. You CANNOT have one good with the other bad. THey are either BOTH bad or BOTH good! Seems anybody that's been around a gun and a chrono and paid attention would know that!
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No. Grouper knows everything. Al's decided to use ES only, we shouldn't have assumed he meant anything aside form what he posted. That's all fine.

For the rest, Look up the Wikipedia article on SD. It's too technical for most of us, me included, but it does introduce the concept of a confidence interval.

So, from http://graphpad.com/support/faqid/1381/

Most people are surprised that small samples define the SD so poorly. Random sampling can have a huge impact with small data sets, resulting in a calculated standard deviation quite far from the true population standard deviation.
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If you want to predict what might happen when you fire a 5 or 10-shot group in a match, and your sample size when testing was 10 shots, ES will probably get you closer. If you're willing to put the rounds down the barrel for a better predictor, a good SD number will be a better predictor. And if you see a lot of outliers when running the SD test, you've got a problem that needs to be addressed.

Now whether or not it s worth the barrel life to get good SD numbers is a different question. I don't think it's worth it. My only point here is to be aware of the information the numbers convey.
 
I should correct myself. While I knew what I meant, I chose the wrong phrase, SD is categorized as a measure of dispersion. It is literally the average distance from the mean. If the average distance from the mean (SD) is small, then the weights or velocities or whatever set of values you are working with are more tightly bunched up around the average (mean), than if the SD is larger. The calculation is relatively simple. Calculate the mean, subtract all of the values from it, square all of the differences (This gives you all positive numbers.), average the squares, and then take the square root of that number. My apologies for the error. It has been about 44 years since I took statistics, and I made the mistake of working from memory.
 
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The little I have learned about reading numbers is that the answers are not of all that much value if you are not asking the right questions or using fuzzy data.

I am just a novice at this game; so please bear with me. Let’s says I live in the east and I want to go to a four day group shoot in the west. I’ve been studying the past and present weather trends and I know the elevation; I feel confident my preloads will work good. I use the proper procedure and I preload 300 6ppc rounds with my favorite 133. The morning of the shoot, I am somewhat worried, Mother Nature just took a turn and the temperature is now 20 plus degrees different than what I thought it was going to be with heavy rain. So I say to myself well at least the humidity won’t effect my preloads. First match starts and I am thinking I should be just drilling these things but I am not, maybe it’s me. Anyway its only warm up I’ll keep trying. Next match same thing and now I am thinking that this lot of 133 is more temperature sensitive than I thought. Right well no problem I’ve brought all my loading gear and there are a lot of shooters so I will just have enough time to use my procedure. And then; oh no, my powder has not had time to adjust to the current climate and I have no clue where to start.

I am not saying that weighing does not add value just that there are other mechanisms of equal value if not greater. I do think the best metering powders also produce a couple other advantages too but, who knows………..

Best of the Season

Ken
 
NOT MUCH WRONG WITH WHAT YOU SAID EXCEPT FOR PRELOADING N133 IN A 6 PPC FOR A GROUP MATCH...

ok
yes you are correct....but it has been documented, well documented, that one cannot throw n133 PRECISELY.
with a top name thrower and n133 typical throws are plus or minus 0.2 with occassional .3's thrown in.....
so while n133 seems to have a large soft window , it is not perfect and will bite you in the azz given half a chance....

and no i doubt if one is using n133, there is no greater issue than precision charges.....

but its just me, and i gave up on n133 long ago.
mike in co

K Hope said:
The little I have learned about reading numbers is that the answers are not of all that much value if you are not asking the right questions or using fuzzy data.

I am just a novice at this game; so please bear with me. Let’s says I live in the east and I want to go to a four day group shoot in the west. I’ve been studying the past and present weather trends and I know the elevation; I feel confident my preloads will work good. I use the proper procedure and I preload 300 6ppc rounds with my favorite 133. The morning of the shoot, I am somewhat worried, Mother Nature just took a turn and the temperature is now 20 plus degrees different than what I thought it was going to be with heavy rain. So I say to myself well at least the humidity won’t effect my preloads. First match starts and I am thinking I should be just drilling these things but I am not, maybe it’s me. Anyway its only warm up I’ll keep trying. Next match same thing and now I am thinking that this lot of 133 is more temperature sensitive than I thought. Right well no problem I’ve brought all my loading gear and there are a lot of shooters so I will just have enough time to use my procedure. And then; oh no, my powder has not had time to adjust to the current climate and I have no clue where to start.

I am not saying that weighing does not add value just that there are other mechanisms of equal value if not greater. I do think the best metering powders also produce a couple other advantages too but, who knows………..

Best of the Season

Ken
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Here's another form of data gathering. If it's already been mentioned in this 40-post thread, I apologize.

What do the winning shooters do? For short range, pretty sure Wayne Campbell and Jeff Summers still throw charges, and Larry Costa still weighs. These are just the top guys I encounter at matches, there are plenty of others. How about the top 20 at the Nationals and Super Shoot?

I don't know any long-range shooters who still throw charges. Tooley use to, for the first 25%-33% of his 81 lifetime points. (That puts him 16th place, lifetime. Not bad for an occasional competitor.) But I believe even Dave went to weighing charges in the end.

Seems to me if you're going to find out how successful a technique can be, see what successful people in fact do.

* * *

As a note, I don't know anybody who can't throw better than +/- .2 grains with N-133 using a Hensler thrower. More like +/- 0.075, with an occasional charges as bad as 0.15. Stiller was going to make a run of these, don't know if he ever got around to it. Downside is the entire adjustment range is around 8-10 grains of powder.
 
Boyd Allen said:
I should correct myself. While I knew what I meant, I chose the wrong phrase, SD is categorized as a measure of dispersion. It is literally the average distance from the mean. ... Calculate the mean, subtract all of the values from it, square all of the differences (This gives you all positive numbers.), average the squares, and then take the square root of that number.
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Boyd,
You have the right calculation procedure, but because the squares are averaged, not the deviations, SD is not the average deviation. The average deviation would be the average of the absolute values (without the squares). One SD includes 68% of a normal distribution of samples, that is the usual definition.

Cheers,
Keith

Grouper,
ES and SD are only proportional so long as the distribution remains the same. You can have on the low end ES = SD, and on the high end ES enormous compared to SD.

That's why I like SD better as the indicator of the potential of a particular load. Bad ES can be the result of untold gremlins, which may or may not be related to the load. (Put another way, SD takes into account ALL your shots, while ES only uses two - the worst ones.) Although, in the end, you gotta exorcise the gremlins, too.
 
mks said:
Grouper,
ES and SD are only proportional so long as the distribution remains the same. You can have on the low end ES = SD, and on the high end ES enormous compared to SD..
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What I meant was taken from the context of working up multiple loads with small samples. In chronographing ammunition, typically there are not enough rounds fired to get ES's wide enough and still let SD remain low. So, someone working up loads with several different combinations will see the ES and SD correlate and go in same directions. However, if you were to pick one of those loads and shoot a thousand rounds of it, yes, you could see high ES and low SD. But not always.
Also, in chronographing ammunition (working with relatively small samples compared to some other calculations), the only time I have ever seen the ES = SD was when they were zero. But that hasn't happened very much!


mks said:
That's why I like SD better as the indicator of the potential of a particular load. Bad ES can be the result of untold gremlins, which may or may not be related to the load. (Put another way, SD takes into account ALL your shots, while ES only uses two - the worst ones.) Although, in the end, you gotta exorcise the gremlins, too..
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I always write down the ES and SD for each load I try. BUt if I could only have one of them, I'd take SD for sure.
 
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To get SDs of any real quality, for a number of loads, requires sample sizes that are larger than I am willing to collect, given the cost per shot, counting barrel wear. Also, I do virtually all of my shooting at 100yd., a distance that does not put as much of a premium on extreme uniformity of velocities. This is why I don't do much chronographing. On the other hand, since there is some thought that velocity can be correlated to accuracy nodes, I find it useful to know the velocities at which these nodes occur, so that I can find them more easily when I make a component change. Obviously this situation would be a lot different if I were shooting at longer ranges. This does not mean that I don't pay attention to things that are known to contribute to consistency in velocity. I do. It is just that my primary reference is group size.
 
Boyd Allen said:
You might want to check this out.
http://www.google.com/url?sa=t&rct=...QZFrPWFXkwkscyAHO1KFQ&bvm=bv.1355325884,d.cGE

Or this, http://www.thefreedictionary.com/standard+deviation

Or perhaps this, http://www.bing.com/Dictionary/sear...n&qpvt=standard+deviation+defined&FORM=DTPDIA
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In the second example in the first link, the deviations are 2, 1, -1 and -2. The average deviation is 1.5, but the standard deviation is 1.58. Both are indicators of deviation, but they are not the same except for some special cases (like the first example with deviations of 2 and -2).
 
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