Misalignment between chamber and barrel bore isn't timing, it's misalignment.
Looking down the bore can be deceiving, if you drop a range rod and snag that ledge, there's your answer.
To alleviate this issue, I take a range rod and a set of feeler gauges to the shop before I ever sign my name to receive any revolver. Pretty straight forward. Either you buy it with the intent to send it back for correction, you don't buy it, or you confirm that your potential purchase has no disqualifying faults.
If you drop a range rod and it doesn't line up, OR if you have 11thou B/C gap, Ruger will replace it. This revolver has both. Why would you not send it in?