well you find a round out in the desert or woods or what, you never know what its been through submerge a bullet into water some go bad some stay good. too behonest i have my share of ammunition in my house for my rifles, largest rifle round being a 50MM round i used for recreational shootin.
im a lil suprised though usually you ahve to hit a bullet with the right amount of force in the right spot to set off the firing pin..believe me that ain't easy.
karma i guess.