I was an Air Force Munitions Officer for 23 years.
Modern smokeless powder (not gunpowder!) is made to last. It's chemically very stable and given half decent storage conditions lasts a very long time. It's not unusual to read/hear about .45acp ammo from WWII being fired and performing just like new.
I should not be surprised that you don’t provide evidence that you understand the basic chemistry of single, double or even, triple based propellants. After all, no one needs to understand EMF and electrolysis to drive an electric car. I did look up your job description at these URL’s:
http://munitionsinsider.blogspot.com/search/label/Munitions Officer
And
http://static.e-publishing.af.mil/production/1/af_a4_7/publication/cfetp21mx/cfetp21mx.pdf
To be an Air Munitions Officer you had to have a College degree, so good for you. I have no doubt you executed your job properly, performing administrative duties, following written procedures with criteria developed by someone else, keeping track of the number of items on your property book and filling out the proper invoices as things disappeared and reappeared. Without a doubt you were aware of “stock pile” reliability programs and “certifications” happening in the background but were not particularly interested in the results except as they affected you as “Go” and “No-Go” . I have met a number of people who understood that voids in rocket motors, as revealed by X-Rays, were undesirable, this was something bad that happens as the propellant collapses inside the binder, but they had no idea of why voids might be there in the first place. And, for their jobs, the why’s, and wherefores of chemistry, kinetics, and thermodynamics, as it relates to propellants, nice to know, but not necessary as long as they follow procedures written by people who do know.
Let me assure all, whether the smokeless propellant is single based, double based, aluminized or not, the fundamental molecule in the mix is nitrocellulose. Which is a high energy compound breaking down to a low energy compound. How nitrocellulose is gelatinized and what it is gelatinized with, to form a single based propellant, is something you need to read about on your own. A goodly portion of the molecules in the mix are stabilizers to sop up the nitric acid gas that comes out of the propellant as it deteriorates. Heat accelerates that deterioration. When enough stabilizer is gone, the propellant is very dangerous to store, and risky to shoot. Hot, moist is probably the worst environment for propellants with Arctic Cold/dry being the best.
There are whole groups of Ammunition Specialists and Insensitive Munitions experts crawling, investigating, testing American stock piles. This is a field into itself but rest assured, they are discarding old ammunition that has met its shelf life. If they don’t, they risk the possibility of ammo dump explosions, and weapon blowup due to burn rate instability, as examples of worst case conditions.
Recently I wrote a long, non mathematical, just a little chemistry, on this very topic at Cast Boolits. Posters were wondering why they were having pressure and corrosion indications with surplus ammunition. The pictures are worth looking at which is why I am going to post the URL.
When milsurp goes bad
http://castboolits.gunloads.com/showthread.php?230264-When-milsurp-ammo-goes-bad
. 
Went bang each and every time.