Me thinks you got a bad thermometer likely. I thought the upper end on the LEE bottom pour was between 750 and 800. I have the 10 pounder.
I also have a LYMAN pot with no dial. That's what I use most of the time. Have only checked it once, long ago. Still casting without measuring. I get more frosty bullets with the LEE than the LYMAN. Too much heat is sometimes a bad thing.