Turning Aluminum Nickel Bronze rings

[The Kevinator]

Ok, so I am turning these Aluminum Nickel Bronze rings, 4.5 OD X 4.100 ID, they are “potato chipping” I.e deforming by as much as .003” out of round.. any suggestions? I need to be round by .001

 

[sfriedberg]

Rough turn, reclamp, finish turn?
Heat treat for stress relief before machining?
Reduce chuck clamping pressure?
Are you starting with tube or plate? What is the thickness (axial length) of the rings?