Luckily I don't have much that's 220 in the house.
Um, by my calculations, you don't have
ANY right now!
It's inconceivable to me that anyone can function without a minimum 200 amp, 120/240 service anymore. I remember the first time that I ever saw a single-pole 50 amp breaker. Yep, it was at my uncle's apartment in... You guessed it. New York City. Central steam for heat and gas for everything else. Go figure.
You'll be fine with the #10 jumper, Sam. Dominion/Virginia Power uses 1/0 aluminum for up to a 300 amp service here, about three-times what it's rated for.
Arthur's right, though. A piece of #6 L.O.G. is good for just about anything. Anything.
