Missed that partIn his first post he states the main panel is full up
I've purchased a two pole 30 amp breaker and matching sub panel and need to wire it into the existing main breaker panel. Most 220 circuits I've seen previouslyIf he puts this subpanel at his main panel, his wiring will be protected. He should ten add another subpanel in the garage at the other end of this wiring.
Like I stated earlier, I wouldn't go through all this without bring a neutral out there for "future" 120v circuits, but that's just me