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"Why would a handloader need such a scale?" a fellow asked me privately in reference to my ad about lab balances in Free Classifieds. "Isn't a tenth of a grain close enough for accurate loads?" I answered him there, with the following --
<br>
<br>CONSISTENCY is the key to the best performance, and charges weighed nominally to the nearest 0.1 grain aren't necessarily that consistent. Consider this:
<br>
<br>A charge that the ordinary powder scale says is (for example) 54.6 grains can actually weigh as little as 54.551 grains or as much as 54.649 grains -- a range of 0.098 grain, which rounds-off similarly to a DIFFERENCE of 0.1 grain while still registering as a "consistent" 54.6 grains. IOW, your "consistent" charges may be different from each other by as much as 0.1 (0.098) grain.
<br>
<br>If you're loading something like 135 grains in a .460 Weatherby Magnum, an inconsistency of 0.098 grain is only about 0.07% of your nominal charge weight. If you're loading my old favorite .38 midrange load of 2.5 grains, that same "little" error is 3.92% of the charge weight that you think is always and only 2.5 grains.
<br>
<br>I think it was Phil Sharpe who wrote (in his Complete Guide to Handloading, I think), without any explanation as I recall, something to the effect that to weigh accurately to the nearest 0.1 grain (0.100 grain), the scale had to be accurate to the nearest 0.001 grain. He was right.
<br>
<br>Consider also that you can trust a good scale only when it's new, clean, unworn, and set-up properly (level, steady, etc).


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On the ads forum, a pal asks what's the heaviest charge that either of these super-accurate analytical balances can weigh. Answer:
<br>
<br>MAXIMUM charge weight? Not to worry!
<br>
<br>the Mettler -- 2,469 grains
<br>the Ainsworth -- 3,071 grains
<br>
<br>On either balance, then, you can pile several charges on the pan at once and find their average weight and their over-all error, down to within 0.00154 grain (1/648 grain).
<br>
<br>And of course you can weigh and sort bullets very accurately -- or by lightly sanding the bases or tips of the slightly heavier bullets, you can bring 'em all very precisely to the same weight within very, very fine tolerances -- a persnickety experimenter's dream!
<br>
<br>(Wet, perhaps?)


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I'm not sure where Phil Sharpe came up with ones needing two orders of magnitude more precision in the measuring equipment versus the tolerance to be held. I was taught in both Chem classes, and as a machinist, that a single order of magnitude was going to be "good enough". Thus a balance that is accurate to .01 grain is appropriate to accurately measure differences of .1 grain. And a micrometer that accurately measures to .0001" is needed to be sure you are holding tolerances of .001". And of course neither a brand new digital micrometer nor a lab balance, is worth a hoot until it is calibrated, by equipment that itself is calibrated... onward up the chain until you hit the bureau of standards (NIST?)
<br>
<br>Regards,
<br>Scott



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Two plausible possibilities, Scott --
<br>
<br>(a) my hazy recollection of what Sharpe said is off one decimal point. I thought I indicated that I wasn't quoting him verbatim.
<br>(b) the way to get 0.01 sensitivity was to go to 0.001 sensitivity (IOW, to get what you wanted, you took what was available).
<br>
<br>Thanks to whomever it was who gave me the link showing the used Mettler balance like mine. I'd found it already. (Here it is, in case anybody here is curious about what it looks like.)
<br>
<br>http://www.globeteck.com/shop/ZANBAL1.html
<br>
<br>Q: Should I ask MORE than the $200 I've been asking for? Nahhhhh!


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I can imagine lots of stuff to do with such a scale.
<br>
<br>.1 grain difference in powder? That's a bit too much to worry with, but a .1 grain difference in the PRIMER charge is a whole different ball of wax...... I can imagine other uses the more I think about it. JMO, Dutch.


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These balances have fascinated me for fifty years but never more so than now that I actually have four good ones. The more I study 'em, the more applications and test possibilities come to mind -- involving all components and equipment, not just powder and scales. Along with the three Zeiss and Leitz microscopes and bomb calorimeter already on hand for the Powley Center test lab -- plus of course the pressure equipment and chronographs -- the two balances that I intend to keep will no doubt make possible, easy, interesting, and edifying any number of little exploratory handloading tests and experiments. I'm excited about the prospects that they suggest and make possible for even the "ordinary" handloader with an urge to experiment.
<br>
<br>Two wistful wishes bother me a little --
<br>
<br>I wish Homer Powley were still around to enjoy and inspire some of these experiments. I really miss being able to talk ballistics with him.
<br>
<br>I wish Homer'd had his own such balance[s] at home instead of having been limited to the use of those where he worked (Frankford and Rock Island Arsenals, etc).


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Thought I'd throw in my two cents worth. I've been a metrologist for going on 20 years, and have calibrated thousands of measuring instruments, both electronic and physical/dimensional. I have always found the accuracy claims of powder scales more than a little "optomistic". Particularly the digital scales. When using any device with a digital readout, one has to add to it's basic accuracy plus or minus one count of the least significant digit. Since the least significant digit of all the common digital scales on the market is .1 gr, you have to take whatever the specified accuracy of the scale is PLUS add an additional .1 gr. The reason for this is the device has a threshold as to when to increase or decrease to the next digit. So a reading of 40.0 gr may be 39.96 or 40.05 etc... How they can claim a + or - .1 gr spec is beyond me. I've tried a couple of digitals, and I'm sticking with a good old balance beam for now. I use a digital to sort cases. The best thing you can do is get a good set of check weights that are certified, and cal your scale with them, check it often, and use that same scale all the time. The key is consistancy. Both enviromentally, and in your measuring technique. Also, the general rule of thumb in the calibration field, is that the instrument you make a measurement with, should be at least four times as accurate as the measurement being made. That is, in order to accurately measure a powder charge to within + or - .1 gr, you would have to use a scale that is accurate to within + or - .025 gr. Sorry for the long wind, I have "issues" on this subject!
<br>
<br>Jeff

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UPS just delivered an unexpected goodie -- a digital electronic powder scale from Hornady, which I don't think is in the Hornady catalog in my files. I'll test it carefully, along with three other digitals and a slew of mechanicals, using a set of check weights that have been check-weighed to the nearest 0.01 grain and a standard form that I've printed with blanks to record the "weight" that each tested scale indicates for each check weight and each combination of check weights.
<br>
<br>It's growing increasingly obvious that I'm going to have to find another term to use for the check weights, since using the word "weight" for both the item itself and the number for its response to gravity frequently gets awkward at best and potentially confusing at worst ("the actual weight of the 5.0-grain test weight is 4.92 grains," for example). ""Standard," maybe. "The actual weight of the 5.0-grain test standard [etc]..." would probably be better.
<br>
<br>I'll let y'all know what I find about the typical accuracy that you can expect to encounter in your average or typical handloading scales.


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thanks for the info and your continuing efforts on our behalf.
<br>I have an RCBS digital scale and an old redding oil dampened one, I mostly use the old redding scale.
<br>Bill


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Ahhhh.....Since I'm not the only one with questionable scale weights, Life is indeed good.
<br>Three well recognized scales on hand and they all lie! At least two of them lie, and it never seems to be the same two. They have probably been lying since day one but I only caught them when weighing out 7.0 grains of Unique. Borrowed a friends "Hi-Dollar Digital" and it said all three of them lied, or, all three of mine said the digital lied...not quite sure.
<br>Russ


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Your post brings to the fore a thought that I've been gnawing for a long time -- the conflict between (a) a service that I'd like to offer to all my fellow shooters and (b) the near certainty that I'd be unwise to offer it. I'd LIKE to be able to say send me your scales, and I'll calibrate 'em accurately and send 'em back to you with a data sheet for each one, showing what (for example) each scale SAYS an actual x-grain charge weighs.
<br>
<br>So here's the compromise offer. I've already offered to calibrate the scales of my local friends who'll bring 'em by, and already have a few borrowed scales on hand to be checked. If you plan to visit Ol' Scat here in Stevensville, Montana, or later at the Powley Center, bring your powder scales with you. Together, we'll put 'em through the hoops and over the humps so you'll know, ever after, exactly what they're telling you.
<br>
<br>That's the best I can think of, right now, that's sensible and practical.
<br>
<br>No charge, of course.


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Ken, I am truly humbled by the offer. If memory serves me right, this would be the second offer you have made for that visit. Perhaps, if we both had just the right size hammer, we could beat the truth out of them.
<br>We had this discussion several years back and I believe your thoughts on "proper care" is the only real answer.
<br>That is assuming...there's that word again...the scales are caliberated correctly at the git-go.
<br>I personally feel that no more than six or seven scales out of ten are weighing correctly, as they sit on the bench. I don't mean to the nearest .1, .01, or .001. I am thinking more like a full .9, 1.0 or possibly even more. I would like to suggest to anyone interested they compare weights when the opportunity arrises.
<br>I would also suggest that no one looses a lot of sleep worrying about the exactness of .01, .02, or .1. IMHO there is no need, as long as it is repeatable. I also don't feel this problem is new or unique in any way. I have been reloading for more than fifty years, started somewhere back in the mid / late 1940's, and I never gave my scales a second thought until ten or so years ago. There is no telling how many scales I've owned, traded for and never used, or used once or twice and sold, all on someone's advice that the next model was simply better. Now I ask myself...better for what?
<br>Technology will bring us a "better" scale. But the better part will only come from our own care and upkeep of this very sensitive instrument. As a side note; If I thought I was in danger, or risk of injury, from the use of a scale I would use a dipper. If I thought I needed to split fine hairs, to the nearest exactness available to me, I would most likely grab my old 10/10 O-Haus from somewhere back in the 1960's. You see...Me and this lying son-of-a-gun have this thing, and life is good, if not percise.
<br>Respectfully, Russ


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"I would also suggest that no one looses a lot of sleep worrying about the exactness of .01, .02, or .1. IMHO there is no need, as long as it is repeatable."
<br>
<br>I agree with this -- as far as it goes. But let's look further.
<br>
<br>Whatever the exact "xy.z grains" value may be, consistency from round 1 to round 1,000 is the most important thing, AS LONG AS YOU KNOW THAT CHARGE IS SAFE. Safety is at risk, however, when you adopt a MAXIMUM load from a manual (which we all know is a no-no, which we all know that nearly everybody does) and your scale is seriously out of sync with the scale used in the lab that developed the data for the manual. (Just another good reason to start with charges lighter than the manuals' maximums.)
<br>
<br>I won't know for sure until I've run the tests I'm planning -- and won't run those tests until I've built and leveled the granite-top bench for my lab balance and have mounted and leveled the balance on it -- but I expect to find that the accuracy of typical handloading scales is different at different points along the beam -- not consistently, say, "2.4 grains light" from one end to the other.
<br>
<br>I'd much rather have accuracy well beyond the level that I need, not less than, and to know just what level of accuracy I'm getting. Once it's established that any scale on my bench is accurately weighing x.y grains when it reads y.z grains, I won't need to check it more closely for every-day loading use. But I do NOT want to put blind trust in any scale that just has numbers on the beam and I don't know how accurate those numbers are. I can't check the accuracy of the scales that the other labs use in developing the loads that they publish in the manuals, so the best I can hope to do is (a) assume that their scales are a bit "off," but nobody knows how far off they are or whether their errors are high or low, (b) determine what MY scales really give me, and (c) allow a good margin for the unknowable disagreement between their scale and mine whenever I consult a manual for a load that I want to try. Then -- once I've established my own safe (probably modified) version of the original load -- the exact grain weight of that charge becomes secondary to the round-to-round consistency of the charges that go into my cartridges.


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"I'd much rather have accuracy well beyond the level that I need, not less than, and to know just what level of accuracy I'm getting."
<br>That's the ticket! Dad-blame-it...Wish I had said that! Recognizing a problem and having the ability to solve it are two different hosses. I can only hope we remain astute enough to recognize it when it shows it's ugly face.
<br>You touched on the fact that load data, from the publishers scale, and loads that have been worked up on your scale, may very well be different in "actual" weight. I have often wished I could have compared my scale weights with those I have read about. When I was much younger, and knew just about everything, I tried to duplicate most of their "published data", God was as kind to me then as He is now. Now that I'm much older,and not near as smart, I expect such discrepancies, and keep them in mind, as part of the reloading experience. I would encourage all to do likewise. Because it is in print does not mean it is gospel!
<br>Respectfully, Russ


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"thanks for the info and your continuing efforts on our behalf."
<br>
<br>Thank YOU -- and congratulations for the perceptivity and perspicacity to discern the urge that drives and sustains me. I suppose that I'd probably do some if not all of this if I were doing it solely for my own interest -- but the prospect that what I find will be of use and interest to others is what drives me to keep at it in spite of setbacks, infirmity, and dollar poverty. I'm pleasantly surprised that anyone has discerned my "ulterior" motive.
<br>


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You are most welcome, and dare I say that you can define our campfire here as two seperate entities.
<br>One is to enlighten, and enrich us in our everyday lives and pursuits, at no real cost to us except the time it takes to read. Best defined by your forum.
<br>
<br>Then there is the other that is aimed at enlightening us and lightening our wallets, as defined by Big Stick and his endeavors.[Linked Image]
<br>
<br>But all in all we do appreciate the knowledge to be gleaned here. I even have dusted off my old Canon EV1 and hope to start applying some of the photo techniques you have posted, I actually went to take a picture the other day and the film was already at the end of the old roll that was in it.
<br>So have to go get some new film and take the old one in to see what the heck I have on there.
<br>Could be interesting.
<br>Bill
<br>


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"I actually went to take a picture the other day and the film was already at the end of the old roll that was in it. So have to go get some new film and take the old one in to see what the heck I have on there. Could be interesting."
<br>
<br>Sure wish you were close enough to come rob my freezer of all the good 35mm b&w, color neg, and slide film that I'll never use.


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Yes, so do I. I use to even do my own developing, more as a hobby, but it added another aspect to picture taking, just like reloading does to ones shooting.
<br>Bill


"The 375HH is the greatest level of power you can get for the investment in recoil." (JJHack)
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Then you know how alike and lasting are the two thrills of seeing (a) a print come-up in the developer tray and (b) a loaded round come out of the seating die. I haven't had a place for a darkroom in far too long to be comfortable without one, so I haven't gently rocked a developer tray in decades -- not a good situation for an old Navy photographer -- but the old thrill that still comes with each just-seated round is as fresh as it was in 1952.


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nice comparison, boys, of photo developing and load developing.
<br>
<br>nice irony here, too: you learn the result of your "shot" in film photography through the development process; you learn the result of your load development through the "shots."
<br>
<br>digital photography almost - almost - takes the fun out of photography, doesn't it?
<br>
<br>i still love to shoot 35mm. go to get a scanner to take digital advantage and so some posting.
<br>
<br>keep up the exchanges, boys. i sure like reading them.
<br>
<br>i've still got some unfaced granite slabs. maybe i'll build a table to take advantage and turn that into my reloading bench. hmmm.


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><>fish30ought6<><
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