The Chinese effort as far as is know is mounted on a barge
The Zumwalt (all one of them) will be passed its use-by life before there is a real working rail gun capable of more than 1 shot before replacing the barrel ... a metallurgical problem I believe.
Sorry, your information is out of date. Checked public sources and verified current tech as of Feb. 2018 is getting close to being able to fire hundreds if not thousands of rounds before the barrel and/or core has to be replaced.