Using a milk can as a boil pot, worried about the thickness.

[EscarpmentDew]

I purchased a couple of stainless cans that I want to use for a boil pot. The cans are like standard milk cans but were actually used to import olive oil. I believe the material is thinner than a typical keg and am concerned this may be a big drawback. Can somebody please give me a clue as to what I should be concerned about if anything? I would appreciate a key word to search or something to get me on track to finding these things out. My search led me to the idea of a double boiler, which may be my best option.