[smittygj]

Originally Posted by kernelkrink

The US military seems to worry about storing ammo at high temps also:

Operation Desert Storm: Solar Radiation Shielding Materials for Ammunition Storage

"Abstract : Absorption of heat through high ambient temperatures and solar radiation has proven to have an adverse detrimental effect on ammunition in open storage. "


How much heat are they worried about? Seems about 161 degrees F is what ammo in Saudi Arabia can get up to. And this is ammo for relatively immediate use (months) not long term stockpiles:

Saudi Arabia (SA) Ammunition Temperatures in Open Storage, 1991

I'll second that. I just looked it up in the publications for ammo storage ashore for Navy and Marine Corps and it states that most ammo is designed to withstand temps between 130 and 160 for short periods of time. I further researched smokeless powder, and found that if it has been exposed to temps above 105 for more than 500 cumulative hours, it should be suspect until lot testing can be done to see if there is any degradation of the ammo.