Ammunition, while seemingly inert, is a complex chemical and mechanical system. Over time, various factors can degrade its performance and even create safety hazards. So, the simple answer is: yes, ammunition can go bad. But the "how bad" and "how fast" depend on several crucial factors. This guide will delve into the details, helping you understand what affects ammunition shelf life and how to best store your supplies.
Factors Affecting Ammunition Shelf Life
Several environmental and compositional elements influence how long ammunition remains viable:
1. The Type of Ammunition:
- Centerfire Rifle & Pistol Ammunition: Generally, centerfire ammunition has a longer shelf life than other types, potentially lasting for decades under ideal storage conditions. However, the propellant's quality is key.
- Rimfire Ammunition: Rimfire ammunition (like .22LR) is notoriously more susceptible to degradation. The primer's composition is less robust, leading to potential misfires or unreliable ignition. It's generally considered to have a shorter shelf life.
- Black Powder Ammunition: Black powder ammunition deteriorates faster than modern smokeless powder ammunition due to its hygroscopic nature (it absorbs moisture from the air). Expect a significantly shorter shelf life.
2. Storage Conditions:
This is arguably the most critical factor influencing ammunition longevity. Improper storage can drastically reduce shelf life.
- Temperature: Extreme temperatures, both hot and cold, accelerate propellant degradation. Ideally, store ammunition in a cool, dry place. Avoid direct sunlight and fluctuating temperatures.
- Humidity: Moisture is the enemy of ammunition. High humidity can cause corrosion on the casing, propellant degradation, and primer issues. Use desiccants or moisture-absorbing materials if storing in humid environments.
- Exposure to Chemicals: Keep ammunition away from corrosive chemicals, solvents, and cleaning agents. These substances can react with the ammunition's components, causing damage.
3. The Age of the Ammunition:
Even under ideal storage conditions, ammunition will degrade over time. The rate of degradation varies based on the factors mentioned above. While some sources claim decades-long shelf life for centerfire ammo, it's wise to regularly check and test ammunition, particularly older batches.
4. The Manufacturer and Quality of Components:
Higher-quality ammunition, using superior materials and manufacturing processes, generally demonstrates better longevity. However, even high-quality ammunition can degrade under unfavorable storage conditions.
Signs of Ammunition Degradation:
Knowing the signs of degraded ammunition is crucial for safety. These include:
- Corrosion: Rust or pitting on the casing indicates moisture exposure and potential degradation.
- Bulged Cases: A swollen or bulged casing signifies increased internal pressure, possibly due to propellant deterioration. Never fire ammunition with a bulged case.
- Powder Deterioration: While visually difficult to assess, deteriorated powder can lead to inconsistent performance, misfires, or dangerous pressure spikes.
- Primer Failure: This may manifest as misfires or weak ignition.
Testing Ammunition:
While you can't definitively determine propellant degradation without sophisticated testing, you can perform some basic checks:
- Visual Inspection: Carefully examine the ammunition for any signs of corrosion, bulging, or damage.
- Function Test (At a Safe Range): If possible, fire a small number of rounds from the questionable batch at a safe shooting range, observing for any malfunctions or inconsistencies. Always prioritize safety when testing ammunition.
Conclusion:
Ammunition shelf life is not indefinite. Proper storage significantly impacts its longevity and safety. By understanding the factors affecting ammunition degradation and regularly inspecting your supplies, you can ensure your ammunition remains reliable and safe to use. If you have any doubts about the condition of your ammunition, it's always best to err on the side of caution and dispose of it properly.
