Finding a rifle earlier than somebody does NOT make you safe on DayZ. So yes, it might be a "bug" and I agree it should be fixed, but it's not that big of a deal tho.

You guys have ever been in the military or had a relative in the MIlitary? I guess not.
Guns are stored SEPARATED from both Ammunition and Magazines for safety purpose, so it's pretty common to find any gun whitout it's magazines or ammo.
Think about it. You walk into a gun store, and all the weapon you find are hanged to the wall whitout it's magazine. So imagine how it would be in an Army Base.
The way the game weapon spawn now is ABSOLUTELY RIGHT.
It just amplifies in a post apocaliptic world, where you would collect even dog shit if it could help you survive.