I understand ammunition can be store for years and even decades if stored properly. My question is, what about ammo that's constantly exposed to the elements. For instance, the ammo that you use in your carry weapon that's constanly stored in a magazine you carry with you everywhere..... Ive have hornaday taps in my g27 thats been in there for over two years. Can I depend on the integrity of this ammo??? The copper plating has even changed color on the bullet. Is it still reliable? If not how often should you change your ammo in your carry weapon?