I agree, as someone said earlier: "I hope this does not turn in to 'some kind' of a contest".
I was looking for gun parts when a man with a magnificent rifle came to have the rifle's head space checked. The smith/parts store owner informed the man he could not check the head space because he did not have a head space gage for the chamber. The rifle owner left, I informed the owner of the fine establishment I could check the head space on any rifle without a head space gage. He responded with "HOW!?"
I explained there were 3 ways, I demonstrated the easies and fastest, He responded with: "I'll be darned

And I will add, he had head space gages that were different,
F. Guffey