Hi William,
I had a Chief's Special with a similar problem. The way I further narrowed down the problem is:
After measuring the cylinder gags, disassemble the entire crane/yoke/cylinder. Any parts that are cylindrical, including the locking rod, roll on a table or other flat surface. If they are out of true, it will be immediately apparent. The problem with mine was not the locking rod itself, but the ejector rod. Soemtimes, previous owners could have been a bit overzealous when it comes to disassembly/assembly. If it is out of true, it could very will bind the revolver on two or three chambers. Usually, a replacement can be had for cheap money and replacing it will solve the problem.
If the problem appears to be the crane itself, the way to properly find out what's going on (as opposed to eyeballing it. I challenge anyone to tell the difference between a gap .007" from one .009" by just eyeballing it) is to use feeler gauges and measure on every chamber, then compare the measurements with the factory specs.
Try to avoid replacing the crane itself, if you can get away with it. The cylinder gap is critical, and to get the gap spaced correctly you'll likely need thrust washers to take up the slack.
When/if you decide on replacing the ejector rod or locking rod (most likely the causation of the problem, from what you have told us so far), if you go with used parts (say, from Numrich GPC or Jack First), try to get them on the phone and specify either NEW (or New/Old stock) or the best used stuff they have. Replacing bent parts with "new" bent parts is just silly. GPC used to have a good crew of guys working the stockroom, and knew just what you were talking about when you asked for something, but now employ college kids or high school kids to gopher for the parts. Most times, they couldn't tell the difference between a good honest clean used part and a piece of junk. I'd say a good 30% of the parts I order from GPC have to go back just because they are in such poor condition or are incorrect. If I had to buy a part, I'd go with Jack First. Call them and talk to them, and they'll hook you up.
Pz
If you go with replacing parts instead of repairing them, you should replace all the springs involved as well. Older revolver like that might benefit from a simple spring swap. Besides, you're going to have it apart anyways.
