Those duratrax temp guns have been known to be up to 100 degree off.

I use a raytek their suppose to be pretty accurate. I got mine for $50, but now I just touch the top of the head with my hand. If the engines around 230-250F I can touch the head with out getting burnt. (but it is warm to the touch) Guessing by how hot you said the the head was when you touched it, I would say it was 240-260 (maybe more)

I'm starting to use my temp gun less and less know. I know there's a few that won't even use their temp gun some times.