weighting in on volume

Discussion in 'Shooting Accessories' started by JNG, Apr 24, 2008.

Help Support Muzzle Loading Forum by donating:

  1. Apr 24, 2008 #1

    JNG

    JNG

    JNG

    32 Cal.

    Joined:
    Jul 12, 2007
    Messages:
    35
    Likes Received:
    1
    While pre-loading some powder, I pulled out my trusty Lee scoopers. On the scale it said, 70 grains use size xx. Well,I weight them and they came darn close to 70 grains. Next I used my really cool brass powder measure. The kind that a little pole drops out of the middle with load marking etched on it. I filled that up to 70 and then weight it, ~92 grains. So which one is right? I was using 3f swiss, if that makes a difference. Thanks for any help. Joe
     
  2. Apr 24, 2008 #2

    Swampman

    Swampman

    Swampman

    69 Cal.

    Joined:
    Jul 31, 2005
    Messages:
    3,370
    Likes Received:
    0
    I can only tell you that weighing blackpowder on a powder scale isn't the right way to do it.
     
  3. Apr 24, 2008 #3

    roundball

    roundball

    roundball

    Cannon

    Joined:
    May 15, 2003
    Messages:
    22,964
    Likes Received:
    4
    If the Lee products are what I think you're referring to, they were not designed/sized for blackpowder and IMO, should not be used to try and draw any meaningful conclusion about BP charges.

    The standard for black powder volumetric measures is based on using 2F BP and the volume to weight ratio is 1:1...ie: If a BP powder measure is set to hold 100grns volume of 2F BP, that volume of 2F BP will then also weigh 100grns....80=80, 50=50, etc.
     
  4. Apr 24, 2008 #4

    Swampman

    Swampman

    Swampman

    69 Cal.

    Joined:
    Jul 31, 2005
    Messages:
    3,370
    Likes Received:
    0
    That's the theory anyway. Don't weigh your charges.
     
  5. Apr 24, 2008 #5

    trent/OH

    trent/OH

    trent/OH

    58 Cal.

    Joined:
    Aug 4, 2004
    Messages:
    2,408
    Likes Received:
    23
    Although weighing your charges can help you verify if you are throwing charges that are identical, or at least really close.
    A new powder measure should be verified before trusting it to use.
     
  6. Apr 24, 2008 #6

    BrownBear

    BrownBear

    BrownBear

    Cannon MLF Supporter

    Joined:
    Jan 3, 2004
    Messages:
    14,767
    Likes Received:
    235
    Were you just scooping up the powder with the Lee measure?

    I ask because pouring into a brass adjustable measure from a horn or spout on a can will result in more powder-- kind of a trickle effect. Along those lines I ended up enlarging the pour hole in one of my horns because it trickled into the measure real slow compared to my other horns and a pour spout on a can. And as a result it put much more powder into the same measure as you're experiencing. An 80 grain measure I made yielded 80 from a horn with a larger pour hole and from the can with a spout, but when filled using the horn with the small spout. All those were volume measures, BTW.
     
  7. Apr 24, 2008 #7

    Darkgael

    Darkgael

    Darkgael

    45 Cal.

    Joined:
    Jul 5, 2007
    Messages:
    1,002
    Likes Received:
    12
    If you weighed the result from each measure, and if your scale is accurate, then the one which read 70 grs. was accurate. Lee, evidently, does calibrate their scoops for BP since the load chart that comes with the set has charge weights listed for each grade of powder from fg to ffffg, as well as for Pyrodex P and RS.
    What you don't know is what brand powder the measures (Lee and the "standard" sliding measure) were calibrated with. Different brands can and do have widely different weights in the same granulation. (see the article by Sherman Bell in the Winter 2004 Double Gun Journal - "Express Rifle Pressure Variables, Black Powder. A measure that was set to throw 95.7 grs (3.5 drams) threw 98.2 of KIK and 115.0 of Swiss.) Though....in your case, more than 20 grs. is an even greater discrepancy. I suspect that the "standard" measure was calibrated with ffg, the larger particles providing less density. I've meant to sit down and to see what differences there are between different granulations of the same brand of powder at the same volume but I have not done so...yet. Perhaps someone else has.
    Pete
     
    Last edited by a moderator: Oct 27, 2018
  8. Apr 24, 2008 #8

    jtmattison

    jtmattison

    jtmattison

    70 Cal. MLF Supporter

    Joined:
    Mar 17, 2004
    Messages:
    4,685
    Likes Received:
    1
    I found that theory to hold very true with Goex 2f and 3f. I weighed several charges measured by volume and 85 grains by volume weighed 85 grains on my scale.

    I don't know why he had such a difference.

    HD
     
  9. Apr 24, 2008 #9

    roundball

    roundball

    roundball

    Cannon

    Joined:
    May 15, 2003
    Messages:
    22,964
    Likes Received:
    4
    Yes, its not theory, it's fact.
     
  10. Apr 24, 2008 #10

    J.D.

    J.D.

    J.D.

    69 Cal.

    Joined:
    Nov 10, 2005
    Messages:
    3,196
    Likes Received:
    0
    IMHO, it is best to use an adjustable meausre to find the most accurate load, then use that indicator on the measure to meter your charge, regardless of the weight of the charge.

    It won't hurt to weigh the powder charge, once the most accurate load is established, just for reference. IMHO, unless you are competing in the most cut throat competition, weighing charges isn't necessary.
     
  11. Apr 24, 2008 #11

    jtmattison

    jtmattison

    jtmattison

    70 Cal. MLF Supporter

    Joined:
    Mar 17, 2004
    Messages:
    4,685
    Likes Received:
    1
    I agree it's not necessary. I don't weigh charges. I did it out of curiosity.
    The point I was making for Mark is that it can be done with accurate weight to volume.

    HD
     
  12. Apr 24, 2008 #12

    JNG

    JNG

    JNG

    32 Cal.

    Joined:
    Jul 12, 2007
    Messages:
    35
    Likes Received:
    1
    I'm weighting the powder now in an effort to find the sweet load with my gun. I shot yesterday and found 80 grains weighted is dead nuts at 25 yards. That comes to 60 + with my brass volume measure. I'm just scooping it out of a bowl. When I am sure at what it likes, I will make a contraption to measure in the field. Joe
     
    RHensley likes this.
  13. Apr 24, 2008 #13

    roundball

    roundball

    roundball

    Cannon

    Joined:
    May 15, 2003
    Messages:
    22,964
    Likes Received:
    4
    Don't lose sight of the fact that scooping it out of a bowl can result in some powder being packed into the scoop as opposed to the amount a measure might hold if powder is just poured into it.
     
  14. Apr 24, 2008 #14

    Swampman

    Swampman

    Swampman

    69 Cal.

    Joined:
    Jul 31, 2005
    Messages:
    3,370
    Likes Received:
    0
    Black powder constantly changes weight. That's why you use a volume measure.

    Theory is ok, but it doesn't hold water like black powder does.
     
  15. Apr 25, 2008 #15

    ssettle

    ssettle

    ssettle

    40 Cal.

    Joined:
    Sep 19, 2005
    Messages:
    285
    Likes Received:
    0
    Location:
    LumberCity Reedsville PA.
    I've used scale and volume to measure powder and both are very close to one another. I've tried both when shooting my sharps blackpowder rifle just to see if there was any difference. I get the same 2 inch group at 100 yards didn't make much difference at all.. I was using 2F; By the way the scale on the side of a volume measure can be thrown out the window. Your better off filing the numbers off they don't mean much when you use different grades and cuts of powder.
    Compressing the powder after you seat the ball is very important. you want to keep it as close as you can shot after shot. Ss.
     
  16. Apr 25, 2008 #16

    Zonie

    Zonie

    Zonie

    Moderator Staff Member MLF Supporter

    Joined:
    Oct 4, 2003
    Messages:
    28,706
    Likes Received:
    1,337
    Location:
    Phoenix, AZ
    JNG
    I agree with ssette.
    There are some good adjustable brass measures and there are some lousy ones when it comes to the accuracy of the markings on them.

    Of course the measured value on your powder scale is correct and if you were using real black powder, the volume of the pile you measured is the volume that your adjustable measure should have thrown to obtain that amount.
    Most likely, the markings on your adjustable measure are incorrect.
     
  17. Apr 25, 2008 #17

    ResearchPress

    ResearchPress

    ResearchPress

    45 Cal.

    Joined:
    Apr 21, 2004
    Messages:
    955
    Likes Received:
    45
    Location:
    UK
    How much variance in weight is there due to changes in humidity? How much variance in weight will you get using a volumetric measure in constant conditions? My guess is that the volumetric measure will have a greater variance. If you have evidence otherwise I would be delighted to know.

    If powder is stored in a closed/sealed container I am not sure how it would be constantly changing weight - wouldn't it need prolonged exposure to the air for variance in moisture content?

    Some members of the Long Range Muzzle Loader discussion list undertook some basic testing in 2001 to assess the Effects of Temperature, Humidity, and Barometric Pressure on Moisture content of Black Powder. You might find them of interest.

    I would be interested in any results you can point me to of similar testing. The problem with the internet is that there is much opinion expressed, which makes its way into 'common knowledge' but little in the way of evidence to back statements up.

    For long range shooting (1000 yards) I need consistency, and the only way to establish that consistency for a string of shots is to weigh the charges - volumetric measures are not accurate enough.

    And to answer the question at the start of this thread, the volumetric measure that said 70 grains which gave a weighed charge of 70 grains is correct for that brand and grade of powder.

    David
     
    Wichoun likes this.
  18. Apr 26, 2008 #18

    jtmattison

    jtmattison

    jtmattison

    70 Cal. MLF Supporter

    Joined:
    Mar 17, 2004
    Messages:
    4,685
    Likes Received:
    1
    Excellent article David. Thanks for sharing!

    HD
     
  19. Apr 26, 2008 #19

    Dphar

    Dphar

    Dphar

    70 Cal.

    Joined:
    Oct 5, 2005
    Messages:
    4,622
    Likes Received:
    0
    The brass measure in not calibrated right. Swiss will weight heavier than the others but normally they weight light in a volume measure. It is possible that the measure you have was calibrated for a low density powder, bad powder lot or ???
    In a ML weighed charges are OK and are probably best for absolute accuracy. But changing the charges a coupe of grains is unlikely to have any effect that can be seen by most shooters.

    In cartridge guns weighing charges is largely useless. I know the charge weight so I can repeat it but cartridges are best loaded to equal volume to assure uniform compression.

    Dan
     
  20. Apr 27, 2008 #20

    JNG

    JNG

    JNG

    32 Cal.

    Joined:
    Jul 12, 2007
    Messages:
    35
    Likes Received:
    1
    My scales weight correctly as I have test weights. I do believe that my measure is incorrect, I have compared it with a friends measure. The good news, is that with a .535 ball and .15 patch it will shoot better then I can. I do love my GM barrel. I do wish to continue working with different ball, patch and powder charges. At least for me, this is the fun part of firearms.
     

Share This Page

arrow_white