I'm not exactly certain what you're saying here ... possibly worrying too much about the type / range of your temp gun ??
Whenever you touch the warm spots they will hardly ever feel hot to you as WE are all 98.4 or thereabouts - that's far too warm for your cooler blooded snake/s.
The accepted warmest temp for Royals seems to be 92F as far as I know and cool side not really lower than 78F ...
Sent from my iPad using Tapatalk