Col. Batguano
75 Cal.
- Joined
- Feb 10, 2011
- Messages
- 5,038
- Reaction score
- 1,416
If you light 2 open piles of powder, one smokeless, and the other black, the black will burn much faster. However, the situation is reversed when the smokeless powder is contained. Because it is a PROGRESSIVE burning powder, as the pressure increases, so does the burn rate. It happens to some extent with BP, but not so dramatically as with smokeless.
Black Powder burns based upon the exposed surface area; smaller granulation = more exposed surface area. Think of it as burning down from the top of the pile and through conduction. Smokeless burns based on conduction AND radiation, so effectively, as the pressure increases, and the radiation from the heat reaches all the flakes, they all burn at once.
That's why just a couple of grains difference in a cartridge gun load can cause huge differences in pressure, but almost no difference with BP.
That said, if you're going to store the stuff in any quantity, do it in a way that will let it burn openly, (a box with a non-latched lid or a method where the gas can escape) and not have the pressure build up to the point the container will fail catastrophically. That, in effect, becomes a bomb.
Black Powder burns based upon the exposed surface area; smaller granulation = more exposed surface area. Think of it as burning down from the top of the pile and through conduction. Smokeless burns based on conduction AND radiation, so effectively, as the pressure increases, and the radiation from the heat reaches all the flakes, they all burn at once.
That's why just a couple of grains difference in a cartridge gun load can cause huge differences in pressure, but almost no difference with BP.
That said, if you're going to store the stuff in any quantity, do it in a way that will let it burn openly, (a box with a non-latched lid or a method where the gas can escape) and not have the pressure build up to the point the container will fail catastrophically. That, in effect, becomes a bomb.