PDA

View Full Version : why is black powder measured by volume?


troy_mclure
May 5, 2010, 12:47 AM
why is black powder measured by volume instead of weight?

zippy13
May 5, 2010, 01:08 AM
Our forefathers had powder horns and volumetric measures, they didn't carry around powder scales. If you told someone to load three drams of powder, he knew exactly what volume you meant. With the transition to smokeless powder and fixed cartridges, uniformity in charges became more critical. Charging the new ammo by weight was more accurate than by volume. And, standard weights and measures had become more common during the industrial revolution.

Why are US kitchen recipes in volume measures (cups and tea spoons) and by weight in Europe?

Hawg Haggen
May 5, 2010, 04:40 AM
Actually you can measure real bp by weight because it's bp they based the smokeless weights on but you can't weigh subs the same way because they're lighter.

B.L.E.
May 5, 2010, 05:58 AM
Black powder can be weighed of measured volumetrically because muzzleloading powder measures are calibrated to black powder.

If Pyrodex listed recommended charges by weight, you would either have to calibrate your powder measure with a scale or you would have to buy a Pyrodex specific powder measure because Pyrodex is less dense than black powder.

So to make it simple, Pyrodex and other subs list charges by volume.

For cartridge reloading, a lot of the black powder substitutes actually do give recommended charges by weight instead of volume and the loading data will state "grains of powder by weight".

ClemBert
May 5, 2010, 08:03 AM
As others have said you CAN measure BP by weight since theoretically 40 grains by volume from your powder measure should weigh 40 grains. When loading cartridges I weigh my charges of BP. More specifically, if I want 40 grains of BP I calibrate my Lee powder measure to throw 40 grains of BP by weight and verify it on a scale. Obviously, the Lee powder measure isn't weighing the powder but rather is volumetrically throwing the powder.

http://media.midwayusa.com/ProductImages/Large/540522.jpg

Delmar
May 5, 2010, 03:37 PM
Actually you can measure real bp by weight because it's bp they based the smokeless weights on but you can't weigh subs the same way because they're lighter.
______That is probably the clearest most concise answer to that question that I have seen.

wogpotter
May 5, 2010, 04:10 PM
Apart from the loads dispensed while setting up the powder meter even modern smokeless loads are actually thrown by volume.:eek:
(Unless you weigh every charge individually individually that is):D

Doc Hoy
May 5, 2010, 04:16 PM
I wonder how many shooters in the 1820s through 1840s measured their powder by the handful?;)

FL-Flinter
May 5, 2010, 08:00 PM
Black powder is hygroscopic and will readily suck moisture from the air making for radical variations in mass. The components themselves will also cause radical variations in mass from lot to lot. Because the mass is highly variable, black powder should only be measured by VOLUME (exceptions made for very experienced persons primarily in the realm of BPCR)