I looked around online and answers ranged from no shrinkage to 6%. For my first attempt I split the difference (3%), then measured the actual diameter with cali

I looked around online and answers ranged from no shrinkage to 6%. For my first attempt I split the difference (3%), then measured the actual diameter with calipers. Also I tended to err on the side of making the ring too small, as it’s pretty easy to remove material from the inside of the ring.