Campagnolo SR cassette and R chain

You dont measure a campag chain that way. You measure witha vernier over 6 links and the distance should not exceed 132.6mm which is equivalent to 0.5% wear approximately.by the time a campag chain has got to 0.75% you could have reached the cassette. The chain come with documentation on this. This can downloaded. I would suggest remeasuring the chain. I say this as I might have the cassette if I know the exact amount of wear on the chain. I am assuming that casstte has only been used with that chain.