[jaketodd]

When a cartridge is fired, the primer is struck and the pressure of the primer increases until it ignites. Since, to my understanding, pressure is the same as heat, how much heat is required to ignite the primer?

Thanks,

Jake

[JonM]

between 300-450 degrees. if your asking about this for keeping ammo in a hot car, it does not get hot enough anywhere on the planet in any container to cause a primer to go off.

dont store ammo or guns in microwaves or ovens or any other appliance. yes morons have done it and killed people storing guns in ovens

[c3shooter]

And the firing from impact is not heat- it is percussion. All explosive materials can be detonated by shock- how MUCH shock is determined by the sensitivity of the explosive. Things like Compostion C-4 are very insensitive- shoot bullets into with no effect. Others, like Fulminate of Silver are SO sensitive it cannot be handled at all without going bang. Primers use lead azide, which is pretty touchy- a good impact is the energy donor to cause it to fall to its lower energy state- releasing energy as it does so.

But unless your car is on fire, it should not make a primer fire. Think about all of the ammo in the sun, in an ammo can, in a truck- in Iraq.