Sometimes I wish I had an electrical outlet at the field to do that, but warm weather also helps. I use a 5X3 prop for the first starts, and often resort to the electric starter to get it going. After a few runs it usually starts by hand, but your correct about a cooling prime causing it to bind.

I hand started my first Norvel .049, and beat my poor finger almost bloody before I got it going! Now I keep the electric starter at hand, and don't hesitate to use it. I always check to be sure the engine is not hydraulic locked, or flooded before using the starter.

Bill