My name is ***** ***** I am happy to help. As a firearms instructor, I receive this question a lot. While not impossible, it is very unlikely that the round will "go off". Ammo should, in theory be kept at normal room temperature, but there are studies that have been done where ammo can be raised well above room temps and won't go off. There is another issue though of the heat warping the shell casing and causing an issue with those cartridges when you do plan to fire them. Think about a glass jar with a metal lid that is stuck. You run it under hot water and the lid expands, loosening it. The brass from the casing can warp as well.I would suggest keeping the gun in a lock box or some shaded area to minimize the exposure to heat.Hope that this is helpful! If you have no other questions, please remember to complete a positive rating on your screen now so that we can close out the question.
I cannot imagine that anything to do with high temperatures in the car could cause a firing pin to retract and go forward, striking a live round.If you want to be 100% safe and sure, just unload the gun when its not in your immediate control.