[Schumi]

If by finish you mean the difference between blued, black, or polished? What is the frame made of, aluminum with a stainless barrel? All Stainless?

The finish is most likely just an e-coating or anodizing. Anodizing does affect the thermal conductivity on the surface of the material, but only on the oxide layer of the coating, which is about 0.001" thick. The rest of the material will have the same K value, and therefore thermal conductivity as any other.

Unless its a composite frame, you won't be able to tell a difference in thermal properties between the finishes of say stainless or gun metal. The heat transfer properties between aluminum and stainless are far different (stainless will conduct heat slower, and hold heat longer, than aluminum) but I take it the slide/frame is all the same base material and they just coat it differently. I'll admit, I'm an engineer; I don't know a lot about pistol construction.


*Edit- radiation doesn't apply to the above, and it based on emmisivity/absortivity of the material. In this case, black would be worse than stainless, if it is out in the sun. but I doubt you're going to be leaving this out to bake in the heat.