yeah, this seems like a hard one to get an answer to. there are many variables..You'd think with how important temps are, though, that more people would be interested in this..
Here's an idea:
Post your chams current temp and tell whether he/she's basking or not!
I'll start: Male panther, 1 yr of age. 73 degrees and just started basking.
LOL-I just went around to all my cages and "shot" all of my chams. It is a cool day in Florida and all are sitting under their lamps. Most have a skin temp of right around 80-with the male Veileds a tad bit warmer (basking monsters that they are) at 84-86.
i understand it depends, as exctotherms can only get as hot (or cold) as their heat source allows. And therein lies my point: there seems to be a lack of information about actual skin temps of these lizards (yet everyone wants to get into a fuss about what watt bulb is appropriate). Wouldn't it be nice (or at least productive?) to have an idea of at what temperature the skin will actually start to burn? Or what may be considered a normal range of body temperature? Obviously, this animal's ability to thermoregulate is extremely important to its chemistry, and I think the more we can learn about them the better. My .02 cents.
For instance, my animal (panther) has never had a burn. Thus far in my collection of temps, I've never got him at above 86 degrees if I remember correctly. I'd be interested to see if anyone has routinely reached higher temps successfully.
I have a reptarium mesh screen and I think that adds a degree of difficulty to the temp gun. Or maybe I'm just really bad at it...anyway, "it depends" is really the answer. I can get a different temperature depending on where I start.
I have a Fischer's so his basking spot is going to be cooler than a panther or veiled. I'm getting 78 degrees to 83 degrees.