Happened to me once.
Comanche 260. 1959. 12 Volt starter motor, good for about 3 tries
Dodgy left mag. Impulse mag. No Sparks. The way to fix it is to hit it with a short metal bar, then turn prop backward once and then one turn normal rotation. This method confirmed by Comanche Owners Club USA.
Anyway, long story short version, in a hurry to get to a business meeting jumped out, did the mag bit and turned it once normal rotation and it started. Stupidly I had left the ignition on and throttle slightly open. Grass airfield and wet grass. Aircraft started to move towards me and the spinner hit me in the chest.
The only thing that saved me was the long spinner on the prop, but it caught my trouser leg and inflicted a cut or two.
I managed to get out of the way then had to run around the entire aircraft as the door is on the other side as it was taxiing towards a building. Just made it in time before a complete disaster took place, as opposed to chopping me into bits.
Lots of embarrassment but it was a really crappy day and an instrument rating day, and there were no witnesses, at least no one owned up.
Gave me a lot to think about. I promised not to kill any more chinamen