Smarter Every Day (2011) - Season 1 Episodes and Ratings

Usually when people see a fireball they are quick to call it an explosion or a detonation. In actuality, what they've witnessed is a type of explosion called a "Deflagration". Many things are deflagrations. Logs burning in a fireplace are Deflagrating. The primer inside the shotgun is actually detonating. Lead Styphenate or Mercury Fulmanide are used in cartridge primers to start the pyrotechnic train in a bullet/shell. The primer itself is detonating, which kicks off the gunpowder which burns in the shell. Any powder detonations occur in the chamber. As the powder burns and begins to push the projectile out (gas seals with the barrel with something called an "obteration seal"). The powder in the barrel is also deflagrating.