Depending on the exact primer composition, a cookoff would require about 325 degrees F. Anyone who claims ammo is cooking off from sun exposure is a liar plain and simple.
Ammo can be degraded over time with high heat exposure, but this may take months or more. I happened to have a vehicle with a thermometer installed in the Middle East and never saw more than 150F inside the closed vehicle.
If you want your weapon cooler, keep it in the lowest point of the vehicle, crack a window, and leave it in a foam lined container. Polymer will remain comfortable to handle unless exposed to direct sun in an enclosed space.
Ammo can be degraded over time with high heat exposure, but this may take months or more. I happened to have a vehicle with a thermometer installed in the Middle East and never saw more than 150F inside the closed vehicle.
If you want your weapon cooler, keep it in the lowest point of the vehicle, crack a window, and leave it in a foam lined container. Polymer will remain comfortable to handle unless exposed to direct sun in an enclosed space.
