There are a lot of nice revolvers out there that make are destined to be shooters because of cosmetic defects.. A common scenario is a beautiful revolver that that has been left in the presentation case and some mild rust ensues.
How does one assess a chamber that has some pitting. What kind of quick check method can one use when you are looking at a chamber in a gunshow that shows it will shoot good.

Chamber pitting will rarely affect revolver accuracy, assuming it's not too deep. What it can do is make for hard extraction depending on how stout your loads are.

In the same vein, I have seen barrels with extensive pitting that shot rather well. Leaded like the devil, but shot OK.

Buck

I never worry about chamber pitting, unless is it really gross. A good cleaning will usually be all that is needed for normal shooting. If it is a .357 that has been shot a lot with .38's it may have to be "deleaded" or the .357's may stick or be hard to chamber. Same with .44 mag shot with 44 specials, or any other "dual chambered" caliber.