Still feel stupid about "black powder equivalent" weights

Discussion in 'Blackpowder' started by Tallbald, Feb 11, 2015.

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  1. sage5907

    sage5907 Member

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    I don't think black powder by volume is the same as black powder by weight. For example, if you measure 100 grains of Goex FF black powder by volume it will weigh about 105 grains by weight.
     
  2. BCRider

    BCRider Member

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    Sage, that's why the folks in this thread have been saying that the volume measurements are only approximate. YOUR measure is dropping a little heavier weight then some. From testing my own measures with Goex I was finding that they drop a little LESS weight.

    In the end though it is the WEIGHT that would matter if you were trying to get the last little bit out of your gun. Which is why serious match black powder cartridge and MLAIC competitors do not measure their powder by volume. They weigh out each and every charge.

    It's really no different from smokeless loading. Benchrest shooters and others serious about accuracy weigh EVERY charge to something more accurate than a tenth of a grain. The rest of us find a Lee dipper or set a powder measure to supply a volume that is close enough to the desired weight and live with the slight variation that goes with using a volume measure.
     
  3. sage5907

    sage5907 Member

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    BCRider, I had been following the Cutrich.comBPconversion chart which lists the weights to volume. The following applies to FFG but FFFG is listed on the chart also.
    Volume cc: 6.67
    Volume grains: 100
    Goex FFG: 104.6
    Jim Shockey Gold: 88.3
    Hodgen Tripple Seven: 77.2
    Pyrodex P: 76.0
    By looking at 100 grains it is easily converted to percentage. I weigh all of my black powder charges to get the best consistent accuracy. Thanks for the response.
     
  4. mykeal

    mykeal Member

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    Interesting stuff. But...

    Nobody establishes the accuracy of their equipment, which, after all, is of utmost importance. Was the volume measure used to create the Cutrich.com conversion chart accurate to 4 decimal places as suggested by his data? We don't even know if it was accurate to 2 places; he doesn't provide any error data for any of his measurements, volume or weight.

    The only reason for measuring charges, using either volume or weight as a metric, is to ensure consistency. Comparing your measurements with other people's data is essentially nonsense unless you know your equipment and theirs produce the same errors.

    Must be wintertime. Somebody throw another log on the fire. And while you're up....
     
  5. BCRider

    BCRider Member

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    Curtrich's chart is a bit messed up. Why?

    There IS NO SUCH THING as volumetric grains. Grains is a measure of weight, not volume. The volume equivalent is just something that black powder folks made up and use as a convenient way to measure our powder out in the field.

    So right off the first line where it says 100 gns of Goex FFFg weighs 101.1gns is wrong. By definition 100gns/weight of black powder is 100gns/volume.

    Now what he SHOULD have done is measured the volume in CC's for 100gns of each of the popular brands of black powder to arrive at an average which would then be used to equate to 100gns/volume. That would be something useful.

    Again there is no recognition in science or engineering of any sort of volumetric measure called "grains". So it's clearly something we BP'ers made up way back in the past. It's simply not a standard of any sort other than the link to being the volume for100gns/weight of black powder.

    The fact that the volume for 100gns/weight of the different brands and grades varies a little is something that the old timers apparently glossed over. Or they would use different 100gn/volume measures as required to drop 100gns/weight for various brands or grades as they came to use them.
     
  6. TimSr

    TimSr Member

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    I think everybody is saying the same thing. The confusion is a result of sequence of history. I'm just making an educated guess, but I'm thinking that cartridges were probably charged by weight pretty early on in their history, while non-cartridge arms were probably loaded by volume long before a weight standard was ever applied, and volume loading was standard practice long after. I am aware that some match shooters like to weigh their charges for more precise consistency. When I said "nobody", I was not speaking literally. I thought the OP was just looking for a starting point to try some equivalent in place of black powder. After rereading I see he is making paper cartridges.

    The Hogdon 25th Edition reloading manual lists Pyrodex equivalent to BP counterparts by weight. It also lists load data for Pyrodex in cartridges. This is before 777, but I would suspect that new Hogdon load data manual would have less confusing cartridge load data like the old one.
     
  7. TheRodDoc

    TheRodDoc Member

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    I guess the younger gen didn't learn about weights and measurements in grade school. We learned it way back in country school days.

    The grain is from the avoirdupois system of weights and measurements that was a British system from before Henry the VIII's time, and is used in US still today. It's one of the smallest measurements in our system. (grains, ounces, pounds, tons and etc). (Not Metric)

    The “grain” also happens to be the same in avoirdupois, troy, and apothecaries UNITS OF MASS.



    The measures we use for our powder are volume measures. Period!! They can be used to measure the volume of anything you might put in them. The Words (Powder Measure) are used to sell the measure to a specific croud. All of you. But the measure itself has nothing at all to do with the weight of Black Powder.
    These volume measures we use for our powder are used and marked the same way that our cup and oz's are.

    1 cup = 8 oz. or 3500 grains.

    Now it doesn't take to much to realize that 1 cup of feathers won't weigh 8 oz. Or 1 cup of lead won't weigh 8 0z. But they will both ocupy the same space.

    The same thing goes for our powder measure. I could set it at 100 grains and fill it with ground feathers or lead bb's and neither will even come close to 100 grains because both have greatly different densities. But again they will both ocupy the same space.

    So being a person can put things of different densitys such as above in the measures, What standard was used to make them? For sure it wasn't lead or feathers, or gun powder for it all has different densities as well.

    WATER!! It is the only substance in the world that always has the same density since the beginning of time and anywhere in the world.

    The weight of distilled water at the temperature of 62 Fahrenheit the barometer being at thirty inches Is the standard used by the world. This includes US and metric measurements.

    To make a 1 cup measure you would weigh out 8 oz. distilled water or 3500 grains if you like then make your container hold that amount. Mark the measure 8 oz. or 1 cup

    To make a 100 grain powder measure weigh out 100 grains of distilled water and make your measure hold that amount. Mark the measure 100 gr.


    The measure above was made for our system but it could be made with metric marks on them too. water weighed the same but metric weights. milligram, drams or cc if you like.

    distilled water weight is also used to make Our gallon and all our other weights and measurements. Even our bushell.

    This water standard makes all volume measures to be the same anywhere in the world.

    The reason we use a volume measure for black powder is that it is the only way to compare powders performance between brands or even lots from the same brand. Velocities, fowling, pressures and etc.
    It is also the only way to acurately write down or tell someone how much powder a certian case will take to seat the bullet properly. If we used weights every brand of powder might sit at different heights in the case because of density, moisture content or ingredients used to make it. It would also be useless to compare different powders by a certian weight.

    Someone here posted the advertised weight of a cartridge powder from way back. And said there was now way to get that amount in a modern case. But that weight was only for that specific powder at that time. Powder company's have always experimented with densities, moisture content and even ingredients so there would be no way to compare then to now. If those company's would have printed volume instead of grain weight on their box we would be able to compare.

    (The “grain” is the same in avoirdupois, troy, and apothecaries units of mass.)


    1 grain = 1/7,000 pound = 1/437.5 ounce

    1 dram = 1/256 pound = 1/16 ounce

    16 drams = 1 ounce or 437½ grains

    1 milligram = 0.015 grain

    1 grain = 64.798 91 milligrams (exactly)

    1 ounce, avoirdupois = 437.5 grains (exactly)

    1 gram = 15.432 grains or 0.035 ounce, avoirdupois

    1 pound, avoirdupois = 7000 grains (exactly) or 453.59237 grams (exactly) or 256 drams or 16 oz.



    A quick simple google search found these.....

    http://books.google.com/books?id=LHdMAAAAMAAJ&pg=PA587&lpg=PA587&dq=an+avoirdupois+measurement,+based+on+water+weight&source=bl&ots=0NUv6I10-Y&sig=qqdsqJaugNbcjr2ZtJt1dQ0okSw&hl=en&sa=X&ei=uNXEUp20HKSwyQGTuIHICw&ved=0CFEQ6AEwAjgK#v=onepage&q=an%20avoirdupois%20measurement%2C%20based%20on%20water%20weight&f=false

    http://books.google.com/books?pg=PA587&lpg=PA587&dq=an+avoirdupois+measurement,+based+on+water+weight&sig=qqdsqJaugNbcjr2ZtJt1dQ0okSw&ei=uNXEUp20HKSwyQGTuIHICw&id=LHdMAAAAMAAJ&ots=0NUv6I10-Y&output=text

    http://books.google.com/books?id=1K8tAAAAYAAJ&pg=PA1116&lpg=PA1116&dq=avoirdupois+measurement+based+on+water+weight&source=bl&ots=EX597O9XNC&sig=DWaL-EL9K8XAoJp4hJ4pysSJUg4&hl=en&sa=X&ei=hO7EUrurGOmdyQGK7YHYCw&ved=0CGEQ6AEwBzgK#v=onepage&q=avoirdupois%20measurement%20based%20on%20water%20weight&f=false
     
  8. Tallbald

    Tallbald Member

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    Sorry for creating the hubbub....Bub. (grin). Don
     
  9. 45 Dragoon

    45 Dragoon Member

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    Great post RodDoc!!!

    Mike
    www.goonsgunworks.com
     
  10. TheRodDoc

    TheRodDoc Member

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    If anyone wants to know more about the standards used for our weights and measurements this is a modern one. history of US weights and measurements.

    http://physics.nist.gov/Pubs/SP447/sp447.pdf
     
  11. BCRider

    BCRider Member

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    RocDoc, I've read through that history and paper of your link and I don't see anything in there that suggests that grains is linked officially and directly to a water measurement. Could you point out where you found this which led to your post?

    What you posted implies that there is such a thing as an official volumetric measure for "grains". But this just doesn't pan out when we go looking around to find such a thing.

    I see cases in these papers where water is being weighed in grains. But they are all being used to weigh a mass of water which is then used to determine other measures or values. I may have missed something but no where to I see anything that suggests that volumes listed in grains are used for anything directly.
     
    Last edited: Feb 16, 2015
  12. RPRNY

    RPRNY Member

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    For paper cartridges, use T7 FFFg and the Lee 1.6 cc yellow plastic dipper for 30 grs BP equivalent. As per above .85 x BP volume gives you T7 FFFg equivalent.
     
  13. Don McDowell

    Don McDowell Member

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    A shotgun measure set to the 1 dram setting will throw about 75 grs of most brands of 2f blackpowder currently on the market...
    The old dead guys at the factory used a scale to weigh the powder charges...
    Sharps spent a page in their 1875 catalog detailing how to use an apothecary scale and translate apothecaries into grains weight...
     
  14. TheRodDoc

    TheRodDoc Member

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    All the worlds weights and measurements are comprised from the troy grain, Which as I said in my other post is the same as the avoirdupois grain.

    It started as grains of wheat but was found to be inaccurate and changed to water weight. It's to much for me to explain so read this carefully. you will have to scroll up a page or so from the opening page to start from the beginning.


    http://books.google.com/books?id=LHdMAAAAMAAJ&pg=PA587&lpg=PA587&dq=an+avoirdupois+measurement,+based+on+water+weight&source=bl&ots=0NUv6I10-Y&sig=qqdsqJaugNbcjr2ZtJt1dQ0okSw&hl=en&sa=X&ei=uNXEUp20HKSwyQGTuIHICw&ved=0CFEQ6AEwAjgK#v=onepage&q=an%20avoirdupois%20measurement%2C%20based%20on%20water%20weight&f=false
     
  15. BCRider

    BCRider Member

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    I read that one too. But there's nothing I see in there to support the idea that our powder measures are based on a weight of water in grains as you suggested above.

    So that leaves us with the idea that the measures are sized to nominally deliver the stated weight of black powder and that it has nothing to do with water.
     
  16. RPRNY

    RPRNY Member

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    I don't understand passions running even a little bit high on this issue.

    All conventional powder measures from the brass tubes used for black powder to an RCBS smokeless powder measure use volume as a representation of weight. In modern smokeless application, one calibrates the volume to ensure it consistently throws the same weight, but it is measured by volume. With black powder, the assumption is that there is sufficient uniformity of granulation and and insufficient difference in power between brands that a nominal volume will work for all. That the volume is based originally on weight must be understood but then may be regarded as surplus knowledge to need, unless one is of the opinion that exact uniformity of charge is required for each shot, as in BPCR competition, in which case, weighing is to be preferred to a less accurate volumetric representation of weight. The bickering over whether one should use volume or weight is unnecessarily Jesuitical. One is using weight in either case so the choice is between approximation (volumetric measures of black powder) or precision (weighing). For most applications, a volumetric representation of weight will produce sufficient uniformity of charge. If insufficient for one's purpose or taste, by all means, weigh.

    This falls down for substitutes like T7 which are more uniformly grained, smaller grained and, thus, packs more densely. The .85 x BP charge accounts for the fact that a greater weight of T7 per given volume is achieved than for black powder.

    In any event, hardly a matter for heated partisanship.
     
  17. BCRider

    BCRider Member

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    You folks think THIS topic is bad? You should see the thread on motorcycle and bicycle forums about cleaning and lubricating drive chains! ! ! ! :D

    The issue arises when some poor newcomer comes looking for guidance from some search link. If poor or wrong practices and beliefs are allowed to be stated in strong terms with no rebuttal then it leads some poor guy into similar mistakes.

    I'm often proven wrong and that's fine. I know enough to know that I'll never know it all. And that recognized mistakes are a way of learning.
     
  18. mykeal

    mykeal Member

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    Yeah, this has really gotten silly.:banghead:

    Yes, we poor uneducated black powder shooters use the word 'grain' to describe a volume measurement, something the world's governments do not endorse (which some folks would consider sufficient reason by itself:scrutiny:). I suppose it will lead to complete ruin in the next couple hundred years (since it hasn't in the last couple hundred).:rolleyes:

    In the mean time,
    with the possible exception of all the elements in the periodic table...:evil:
     
  19. Don McDowell

    Don McDowell Member

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    It's a fairly simple deal, when talking of blackpowder charges, the "grains" are generally intended to be the real measurement (or relatively close) When dealing with the subs, the "grains" is however much of the stuff fits into a blackpowder measure set for a certain charge. The actual weight of the substitute powder will be considerably less than the actual weight of the blackpowder..
    Not a big deal, but there's a ton of misunderstanding about it all.
     
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