I'm working on a small engineering project that involves putting a microcontroller inside a screw of a light bulb and I need to find what are the typical heat outputs of 60W bulbs and strong (like 20W/2300lm) LED ones. I've found plenty of information from reptile owners about the best lamps to heat you vivarium, but they don't test usual home ones, and rarely for the temperature of the bulb itself.
Wikipedia: "The glass bulb of a general service lamp can reach temperatures between 200 and 260 °C (392 and 500 °F). Lamps intended for high power operation or used for heating purposes will have envelopes made of hard glass or fused quartz."
Assuming the glass reach those temperature ranges, the metal should be near that too.