So what's the recommended number of winds to start running a PO co axial from the zero power reserve state?

 

The actual number of winds to reach full power reserve may depend on the caliber of the movement. I know you can not over wind a modern automatic. With my watches, I manually wind for about a minute then wear them.

 

Ideally with any automatic that is fully run down, you want to give it a good charge before wearing it, this is especially true if you are not very active during the day, i.e. sitting in front of a computer.

These movements require a good 70+ turns on the crown for a full wind, so I would suggest at least 25 turns on the crown. Wind off the wrist, to prevent undue stress on the keyless works.

If it doesn't automatically start running after 25 turns, then place the watch on a table face up, and rotate it gently side to side in a CW and CCW motion to get the balance moving so it starts running.

 

If a modern omega, wind until it's clicking with each turn of the crown. Then you know it's fully wound

 

My PO2500 starts clicking after 50 turns if I remember well. The second hand starts ticking after 5 turns.

 

What counts as 1 "turn?"

I ask because it highlights the beauty of the mechanism and the fact that you can't over wind it!

Turning the crown between your fingertips is not necessarily 1 revolution of the crown. Varies between individuals!

 

In my case, one turn equals to roughly 5 sixth of a real 360° turn, so around 300°. I checked by observing the position of the Omega symbol on the crown.

I just wound it up and this time it took me 3 turns to start the second hand and about 55s to start hearing the clicking.

I guess variation can even happen with the same individual. Manual turns can be shorter or longer using the same fingers, depends on how much thumb is used to roll the crown, the whole width or just the tip.

 

I typically wind my 2500C until I feel is tightening. . . so 15-20 times?

 

Right
It's like saying you pump gas for your car until you've counted to 100

Just continue until the built in safety mechanism releases the handle automatically.

Then you're done.