Several years back we had a fire that severely damaged our home. While some of the ammo in the attic did `cook off' in the fire, a great deal of it did not and was only exposed to high heat. In most cases it was a matter of location, things located on the floor of the attic were far less damaged than things located on shelves, etc. The aluminum bullet trays on the Dillon presses melted as they were located on benches and exposed to very high temps near the celing where heat accumulated. Down on the floor, where the bulk of the ammo was located in plastic cases and boxes, the heat was often just high enough to slightly melt the plastic. Even many of the plastic powder bottles were only slightly melted and the powder looked fine.
The question is, will a short time (an hour or so?) being exposed to heat that was at least a few hundred degrees cause enough harm to loaded ammo to make it unsuitable for use? I know heat causes smokeless powder to degrade, but is 100 degrees storage for years in an ammo bunker or attic really any better or worse than a few hundred degrees for a very short time? I'm not sure anyone has really ever given this much though, but I'm willing to bet that more than a few folks here at The Highroad will have some good input.
The question is, will a short time (an hour or so?) being exposed to heat that was at least a few hundred degrees cause enough harm to loaded ammo to make it unsuitable for use? I know heat causes smokeless powder to degrade, but is 100 degrees storage for years in an ammo bunker or attic really any better or worse than a few hundred degrees for a very short time? I'm not sure anyone has really ever given this much though, but I'm willing to bet that more than a few folks here at The Highroad will have some good input.