Storing ammunition in a garage is a common question when indoor space is limited. The answer is conditional, depending on the owner’s willingness to mitigate the environmental, security, and legal challenges inherent to a non-climate-controlled space. Responsible storage requires addressing factors that degrade reliability and ensuring the safety of the household and community.
How Temperature and Humidity Affect Ammunition
The garage environment presents two primary threats to ammunition integrity: large temperature fluctuations and high humidity levels. Wide temperature swings in non-climate-controlled areas lead to condensation. This occurs when warm, moist air cools rapidly on the metal cartridge cases, introducing moisture directly to the ammunition.
Moisture absorption by the propellant (nitrocellulose) causes it to break down and burn unevenly, resulting in performance issues like reduced velocity or a “squib load.” The ideal storage environment maintains 30% to 50% relative humidity and a consistent temperature (55 to 85 degrees Fahrenheit). High heat above 150 degrees Fahrenheit can cause the nitrocellulose to chemically destabilize and degrade rapidly.
High humidity causes brass or steel casings to corrode, tarnishing the surface and compromising the seal around the primer and the bullet. This corrosion can weaken the casing or cause the round to fail to chamber or eject properly. Primers are highly susceptible to moisture damage, which can render them inert or cause a “hangfire.”
Essential Safety and Security Measures
A garage requires robust security measures against unauthorized access and household hazards. To prevent theft and access by children, ammunition must be stored in a lockable container, such as a steel safe or heavy-duty ammunition can. These containers should be anchored to the garage structure to prevent removal.
Fire is a significant concern, as garages often house flammable materials like gasoline, paint, and chemicals. While ammunition will not typically detonate en masse during a fire, the rounds can “cook off” and propel shrapnel, posing a risk to first responders. Ammunition should be stored in fire-resistant containers, kept a safe distance from combustible liquids or materials.
The security container should be dedicated solely to ammunition storage, separate from firearms. Separating ammunition complicates unauthorized access and allows the storage solution to be optimized for environmental control.
Local Ordinances and Regulatory Restrictions
Before storing ammunition, owners must investigate the specific regulatory environment of their location. Local zoning laws and municipal ordinances frequently regulate the storage of hazardous materials, a category under which ammunition may fall. These rules can be restrictive for attached garages or multi-family dwellings like condominiums.
Homeowners Association (HOA) covenants represent another layer of restriction that must be reviewed carefully. Many HOAs have specific rules regarding the visibility, storage, and handling of firearms and ammunition. Ignoring these local rules can result in fines, legal action, or the forced removal of the stored materials.
Local regulations vary widely, requiring personal due diligence. A review of local building codes may reveal restrictions concerning the maximum allowable quantity of ammunition that can be stored on residential property, sometimes measured by weight or the number of rounds.
Best Practices for Proper Garage Storage
Environmental risks can be minimized by employing targeted storage techniques. Ammunition should be stored inside airtight, water-resistant containers, such as metal military-style ammo cans equipped with a rubber gasket seal. Containers must be placed off the floor on shelving or a pallet to prevent contact with cold concrete and protect against potential flooding.
To manage the humidity sealed inside the container, desiccants like silica gel packets or rechargeable dehumidifying canisters should be placed alongside the ammunition. These materials absorb residual moisture and help maintain the relative humidity below the 50% threshold necessary to prevent corrosion. Desiccants must be monitored and refreshed or recharged regularly to remain effective.
Containers should be positioned away from exterior walls, which promote condensation by transferring outside temperatures. Storage locations must also be protected from direct sunlight, which can rapidly elevate internal temperatures and degrade the propellant. Ensuring containers are not stacked too tightly allows for air circulation and helps maintain a stable temperature.