I've started prepping my first set of practice barrels I picked up for $10. A few questions about prepping and polishing:

There are tiny rust pits on the exterior. Should those be removed by wet sanding? I've started with 180 grit and the spots are much better. I'm wondering if I should drop down to 100 grit, or stay the course and just know that it takes a long time to wear that stuff down. At what point would someone use a draw file?

I have been using 6" strokes. Is that too long? Should I make long strokes while using the heavier grit, or is it okay to focus more aggressively on the small spotted places. Does it matter? I was going to make sure to use consistent strokes when I got to the finer polishing stages.

Do I need to cross sand when I move up in grit? Larry Potter did on a rifle barrel, but that was easy for him since there wasn't a rib in the way?

Thanks for the responses!