I wouldn't worry about shooting things like you have listed above.
I shoot old Galv. Steel garbage cans, 55 gallon drums etc all the time. I have never had a FMJ round go "rogue", always an equal number of entry and exit wounds so to speak.
Keep in mind almost everything you have listed are a very soft metal, like Aluminum and copper. If you were shooting 1/2 steel plates or old cars I might be more worried.
PS: Coins are no match for rifle rounds either