Cold Pilgering

Anyone have any experience getting a mill run of custom stainless tubing? What sort of tolerance on the ID can be held? We are currently making a custom nitronic 60 tube from solid, gun drill/honed, straightened and finished but the roundness and straightness is what is the problem. It's to be expected going from solid and removing most of the material.

ID is 1.625" +.003"/-.000" Wall thickness .040" +.003"/-.002"

We could finish the OD after as long as there isn't too much stock.

Anyone know anything about the process or a non Chinese, preferably American source for the process?

Thanks