I had similar cylinder binding issues with my 66-8 2.75" at first. No problems with jacketed 158 grain bullets, but significant binding issues with 158 gr. cast bullets after 24 rounds. Not a big deal to resolve by cleaning, but annoying. After 600 or so rounds my binding issues seem to have resolved themselves. Last time out 50 rds. of the load that had given me problems before did fine.