Primer Storage and Safety

1. Modern primers, with proper storage, have incredibly long shelf life (in spite of rumors to the contrary that ran amuck in 1993-4). For storage and safety, primers must be left in their original packaging. Find an area with low humidity and reasonably constant temperature. High humidity combined with big temperature swings can degrade primer performance. Any dehumidifying equipment must be flameless to avoid accidents. Check for local regulations regarding the quantity of primers that can be stored in a residence and adhere to those regulations.
2. Modern primer packaging is designed to protect primers from mass detonation in the event they are in a fire or the package is dropped. In a fire, current packaging design results in a series of small "pops" as individual primers cook off.
3. Never store primers near exposed flame or sources of static electricity. Never smoke while handloading.
4. Never store primers in a tightly closed metal container like a ammo can. To do so is to risk a devastating explosion complete with deadly metal fragments from the can. Such confinement can make the discharge of one or two primers instantaneously progress to a high-order event, involving all primers in the can.
5. Never store primers in bulk, that is, removed from their factory packaging and placed in another container. When loading, dump out only ten to twenty primers at a time. When the session is over, return all primers to their original containers before putting them away.
6. If you use primers tubes for automated feeding, keep tubes clean and oil-free. Clean dirty tubes under water and dry thoroughly before returning them to service. Do not store primers in tubes; return them to the original packaging at the end of the loading session. Take care to avoid dropping loaded tubes. Never alter a tube, or use a tube not designed for your loader.
7. Primers are best stored in a vented wooden box or cabinet with a loosely attached door or lid. This allows the pressure to vent in the case of fire or a few primers detonating in the container. Wood acts as insulation to slow the transmission of heat to the primers.
8. Mark primer packages with the date of purchase and use them in the order received. This rotates your stock so no box is forgotten.
9. All reloading components, including primers, must be stored away from access by children or persons with impaired judgment.
10. Always wash your hands thoroughly after handing ammunition or ammunition components.
11. Above all, apply a healthy dose of common sense to primer handling, as well as all your handloading activities.