What is the explosive force of gunpowder in Joules?

I need this for my Research project.What is the explosive force of gunpowder in Joules?
1. Gunpowder does not really explode, it just burns rapidly.





2. There are different formulations of gunpowder and each has slightly different behavior. Gunpowder for fireworks is quite different from gunpowder for a rifle, which is different, in turn, from pistol powder and cannon propellant, etc. (Gunpowder is a mixture, not a compound)





3. The ';force'; is a side-effect of the heat energy and gas that the gunpowder generates when it burns. Unconfined, the force is 0. Thus the force depends on the the extent the gunpowder is confined - its density, burn rate, etc.





4. So, the place to start is with the enthalpy of a representative composition and a simplified burning equation:


http://en.wikipedia.org/wiki/Gunpowder


http://en.wikipedia.org/wiki/Enthalpy


http://en.wikipedia.org/wiki/Standard_en鈥?/a>


If you need more info on this, perhaps you should ask in the Chemistry section.





5. But, if you want a _very_ rough estimate, about 25% of the available energy in the charge becomes the kinetic energy of a rifle bullet. You can get an idea of just how much that is at a black-powder shooting site:


http://pages.sssnet.com/go2erie/muzzle.h鈥?/a>


http://www.chuckhawks.com/index2h.muzzle鈥?/a>