Need 50amp at the Ranch, which romex ???

enblethen wrote:
Not legal to use tape on wire smaller then #4. NEC Art 200.6

I am sure you are correct. But common sense tells me if there is a continuous conduit from breaker to receptacle it would be fine.

I would do it at my own home but on someone else's place or doing it as a licensed sparky ya gots to do it right!