"Powder burns- (deflagrates) it does not detonate."
Correct. Not only does powder burn rather than detonate, it burns fairly slowly when unconfined. In the examples of a thrown cartridge or in a fire, the initial pressure will quickly push both the primer and bullet out and the internal pressure will immediately drop to nearly zero. Nearly zero pressure produces nearly zero bullet velocity and few - if any - case fragments.
Last edited by Fuzzball; 06-09-2010 at 02:30 PM.