Nitrocellulose has double bonded NO molecules. Ionic compounds will break those double bonds releasing NOx which also degrads the nitrocellulose molecule.
Water is ionic, water evaporating on and off the nitrocellulose molecule accelerates the breakdown of gunpowder.
I would say, based on what I have learned, heat is the main enemy of gunpowder. The breakdown of gunpowder is directly related to heat. Then come the effects of water, ionic chemicals.
Section from the Propellant Management Guide:
Stabilizers are chemical ingredients added to propellant at time of manufacture to
decrease the rate of propellant degradation and reduce the probability of auto ignition during its expected useful life.
As nitrocellulose-based propellants decompose, they release nitrogen oxides. If the nitrogen oxides are left free to react in the propellant, they can react with the nitrate ester, causing further decomposition and additional release of nitrogen oxides. The reaction between the nitrate ester and the nitrogen oxides is exothermic (i.e., the reaction produces heat). Heat increases the rate of propellant decomposition. More importantly, the exothermic nature of the reaction creates a problem if sufficient heat is generated to initiate combustion. Chemical additives, referred to as stabilizers, are added to propellant formulations to react with free nitrogen oxides to prevent their attack on the nitrate esters in the propellant. The stabilizers are scavengers that act rather like sponges, and once they become “saturated” they are no longer able to remove nitrogen oxides from the propellant. Self-heating of the propellant can occur unabated at the “saturation” point without the ameliorating effect of the stabilizer. Once begun, the self-heating may become sufficient to cause auto ignition.
Primers, I have been unable to find information on the shelf life of primers. I know they go bad because I have had some very old ammunition with dud primers. But I think primers are more hardy than gunpowder.
Water is ionic, water evaporating on and off the nitrocellulose molecule accelerates the breakdown of gunpowder.
I would say, based on what I have learned, heat is the main enemy of gunpowder. The breakdown of gunpowder is directly related to heat. Then come the effects of water, ionic chemicals.
Section from the Propellant Management Guide:
Stabilizers are chemical ingredients added to propellant at time of manufacture to
decrease the rate of propellant degradation and reduce the probability of auto ignition during its expected useful life.
As nitrocellulose-based propellants decompose, they release nitrogen oxides. If the nitrogen oxides are left free to react in the propellant, they can react with the nitrate ester, causing further decomposition and additional release of nitrogen oxides. The reaction between the nitrate ester and the nitrogen oxides is exothermic (i.e., the reaction produces heat). Heat increases the rate of propellant decomposition. More importantly, the exothermic nature of the reaction creates a problem if sufficient heat is generated to initiate combustion. Chemical additives, referred to as stabilizers, are added to propellant formulations to react with free nitrogen oxides to prevent their attack on the nitrate esters in the propellant. The stabilizers are scavengers that act rather like sponges, and once they become “saturated” they are no longer able to remove nitrogen oxides from the propellant. Self-heating of the propellant can occur unabated at the “saturation” point without the ameliorating effect of the stabilizer. Once begun, the self-heating may become sufficient to cause auto ignition.
Primers, I have been unable to find information on the shelf life of primers. I know they go bad because I have had some very old ammunition with dud primers. But I think primers are more hardy than gunpowder.
