No there isn't a better nock for .204 Id shafts. If they are a little tight just take a light sand paper to them, a couple passes and your good to go. I switch all my Rampages to x nocks as well.
If the nock itself is tight going into the shaft put some string wax on it and rotate it a few times as you push it into the shaft. Wipe off excess and it will hold its position but move easily if you need to rotate