Measure?
- Thread starter Bullet94
- Start date
Well, no.
Black powder is theoretically measured in grains by weight, IF it is true black powder. In fact, most people measure by volume. They use a dipper or an adjustable cavity. It might be marked "40 grains," meaning 40 grains avoirdupois by weight (equals 40/7000 of one pound). It probably throws about that weight of powder. Probably.
Knowing that most people measure black powder that way, the manufacturers of black powder substitutes have set things up so that their products will substitute for real black powder on a volume-for-volume basis. So if I set my measure for 40 grains and fill it with a BP substitute, what I get should be the correct POWER to substitute for 40 grains of true BP. I have hardly an idea in the world what it's actual weight might be, though.
Black powder is theoretically measured in grains by weight, IF it is true black powder. In fact, most people measure by volume. They use a dipper or an adjustable cavity. It might be marked "40 grains," meaning 40 grains avoirdupois by weight (equals 40/7000 of one pound). It probably throws about that weight of powder. Probably.
Knowing that most people measure black powder that way, the manufacturers of black powder substitutes have set things up so that their products will substitute for real black powder on a volume-for-volume basis. So if I set my measure for 40 grains and fill it with a BP substitute, what I get should be the correct POWER to substitute for 40 grains of true BP. I have hardly an idea in the world what it's actual weight might be, though.
As a BP shot that has submitted myself to measuring by volume, remember that 40gr of FFFg and FFg is not the same. With smaller space between the particles of FFFg, due to smaller particle size of FFFg, your volume is more dense, therefore you have "more" powder packed into that volume.
Therefore, apart from faster combustion, you also have more powder to burn once loaded.
Therefore, apart from faster combustion, you also have more powder to burn once loaded.
armedandsafe
New member
Hafoc got it. Heinrich got some more of it. Black powder is measured by weight. Because it is impractical to carry and use scales in the open, measuring by volume is a practical substitute for that operation.
Substitutes are volume-equivalent to black powder in gas production (energy release.) One could, if desired, measure 40 grains by weight of black powder, set a volume measure to just contain that, fill that volume container with substitute, weigh that substitute and then use scales to weigh out the substitute for loading cartridges or speed loaders. I am not sure why I...errrr...anybody would do that, except as an exercise to combat boredom.
Pops
Substitutes are volume-equivalent to black powder in gas production (energy release.) One could, if desired, measure 40 grains by weight of black powder, set a volume measure to just contain that, fill that volume container with substitute, weigh that substitute and then use scales to weigh out the substitute for loading cartridges or speed loaders. I am not sure why I...errrr...anybody would do that, except as an exercise to combat boredom.
Pops
Raider2000
New member
Heinrich said:
Maybe why the .45 Colt cartridge was loaded with FFG instead of FFFG.
"I could be wrong but I think I read some where that the .45 Colt cartridge was loaded with FFG"
I thought I read that black powder could not be measured by weight because it would vary do to the amount of moisture it absorbed, hence the volume measurement. But I thought the volume measurement was based on water weight – volume. I read so much that I can’t remember where I got this other than I wanted to find out if this is correct or not. Anyone know?
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This is the first I've ever heard of the theory that grains volume of black powder actually refers to the volume of that many grains of water. I'm not sure I'm going to accept that idea at this time.
Let's give an example. The .45 Colt, according to my Lee's reloading manual, has a "useful case capacity" (whatever that means) of 1.93cc. Due to the wonders of the metric system that means it would also hold almost exactly 1.93 grams of water. (They set the system up to have that correlation be exact, but this was in the 18th Century. Their measurements were just a bit less precise than ours today.)
1.93 grams of water at 15.432 grains/gram (see www.onlineconversion.com) comes out to 29.78 grains of water. The historical charge for the .45 Colt was supposed to be 40 grains black powder. Modern cartridges have more brass and therefore less volume, but according to some websites I've checked they are still getting 36 or 37 grains of BP into their .45 Colt loads.
So the correlation between grains weight of water and blackpowder grains measured by volume is vaguely close, but only vaguely.
That line about "Can you imagine weighing out powder in the heat of battle, or to get a second shot at a deer?" is correct enough. Thing is, though, that there would have been no need to calibrate a dipper or scoop or what have you to some volume based on some set weight of water.
The hunters weren't that precise. They would have started with some rule of thumb-- one of the old ones is, put a round ball in the palm of your hand and pour powder over it until the ball is just covered by the heap, and that's your load. They'd use some starting point like that, and hollow out a little cup or dipper of that volume, or a little more, or a little less, based on what they thought worked best with their particular gun. Or if the weapon came from a factory packed with all the accessories, some sort of dipper or powder flask spout of the "proper" volume might come with the kit. Calibrating those measures to a certain weight of black gunpowder itself was as easy as anything else, assuming the measures weren't homemade. If they were homemade, they might not have been calibrated to anything at all.
As for the military, at least as far back as the American Revolution governments provided their soldiers with pre-measured gunpowder charges. The powder came in a paper tube cartridge along with the appropriate projectile or projectiles. You bit the end off the tube, poured the powder down the barrel, rammed the ball down on top, and there you were. Again, there's no need to provide any information correlating the volume of the powder with the weight of that volume of water. It's really an unnecessary step.
Let's give an example. The .45 Colt, according to my Lee's reloading manual, has a "useful case capacity" (whatever that means) of 1.93cc. Due to the wonders of the metric system that means it would also hold almost exactly 1.93 grams of water. (They set the system up to have that correlation be exact, but this was in the 18th Century. Their measurements were just a bit less precise than ours today.)
1.93 grams of water at 15.432 grains/gram (see www.onlineconversion.com) comes out to 29.78 grains of water. The historical charge for the .45 Colt was supposed to be 40 grains black powder. Modern cartridges have more brass and therefore less volume, but according to some websites I've checked they are still getting 36 or 37 grains of BP into their .45 Colt loads.
So the correlation between grains weight of water and blackpowder grains measured by volume is vaguely close, but only vaguely.
That line about "Can you imagine weighing out powder in the heat of battle, or to get a second shot at a deer?" is correct enough. Thing is, though, that there would have been no need to calibrate a dipper or scoop or what have you to some volume based on some set weight of water.
The hunters weren't that precise. They would have started with some rule of thumb-- one of the old ones is, put a round ball in the palm of your hand and pour powder over it until the ball is just covered by the heap, and that's your load. They'd use some starting point like that, and hollow out a little cup or dipper of that volume, or a little more, or a little less, based on what they thought worked best with their particular gun. Or if the weapon came from a factory packed with all the accessories, some sort of dipper or powder flask spout of the "proper" volume might come with the kit. Calibrating those measures to a certain weight of black gunpowder itself was as easy as anything else, assuming the measures weren't homemade. If they were homemade, they might not have been calibrated to anything at all.
As for the military, at least as far back as the American Revolution governments provided their soldiers with pre-measured gunpowder charges. The powder came in a paper tube cartridge along with the appropriate projectile or projectiles. You bit the end off the tube, poured the powder down the barrel, rammed the ball down on top, and there you were. Again, there's no need to provide any information correlating the volume of the powder with the weight of that volume of water. It's really an unnecessary step.
armedandsafe
New member
Yes, you will get variations in charge weight because black powder is hygroscopic. However, that change is not significant, if you store your powder properly and are using your scale just to calibrate your scoop/dipper/spout/hand.
I, in the beginning, did use my scale to measure black powder and used that to cut my own measure. That measure agreed quite closely with the commercial one I bought later.
Sometime in the near future, I'll be cutting a measure into a powder horn. I'll use that to get a comparison on volume vs. water weight. It won't be until slack time in about mid-winter, though, so don't hold your breath unless you look particularily good in blue.
Pops
I, in the beginning, did use my scale to measure black powder and used that to cut my own measure. That measure agreed quite closely with the commercial one I bought later.
Sometime in the near future, I'll be cutting a measure into a powder horn. I'll use that to get a comparison on volume vs. water weight. It won't be until slack time in about mid-winter, though, so don't hold your breath unless you look particularily good in blue.
Pops
I’m new to black powder (really triple 7) so when Hodgdon on their web site said to measure by volume I was interested why. Which lead me to do some more reading where I read about using the weight and volume of water to determine the charge. Curiosity has me looking for the answer. If I had some real black powder I could test this myself. Maybe someone with black powder could try weighing some water and comparing the volume to black powder volume and settle this.
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