If you are shooting surplus commie stuff like 7.62x54r or .30-06 from Greece, chances are you are shooting stuff more than a couple decades old.Over a period of many years, or even decades, high environmental heat will tend to degrade the chemistry of your ammunition. It can lead to less reliable primer ignition and variable results in the powder.
If your ammo is less than a decade old, I wouldn't spare a single thought to it. It'll be fine. If you're "prepping," keep your ammo sealed and in a cool, dry place.
I've shot ammo stored in U.S. "home" conditions (non-air conditioned, in Missouri) that is decades and decades old. I just recently shot up some cheap .22LR ammo, generally considered to be the least reliable and most vulnerable type ammo, that was at least 25-30 years old. Even that had only a few failures to ignite.
I think you're probably OK.
Peace favor your sword,