Thanks guys. Yes heat has done that on another stave, but I used no heat on the bow. Pearly yes some of the pins went through to the back, that's why I backed it with rawhide.
I haven't blown a bow up in hand yet, gotta sooner or later. I'm up to a bit over 100 arrows out of this thing, I'll keep going.
This was supposed to be a gift for a friend, but maybe I should just make him a yew bow.
It seems like nearly everyone who has made an OS bow has noticed these marks, but no one has admitted to ever breaking an OS bow because of them. Hmmmmm