Ok, I'm BAAACK from a shooting class over the weekend. I took my S&W 9mm and my new Ruger sp101 to the class. My 9mm functioned flawlessly as usual. (Have I mentioned how much I LOVE that pistol?) However, the new Ruger decided to be temperamental. I was shooting new Federal .38 spl. lead SWC's and once in awhile the cylinder starting binding and then it locked up. I couldn't even cock the hammer SA let alone get anything to move DA. If I opened the cylinder and closed it again it worked fine. This happened 2 or 3 times. Anyone know where to start looking? BC gap is .003", no lead buildup on the front of the cylinder either. Charge holes didn't/don't look fouled and the ammo doesn't seem to have any high primers. There is/was no indication of interference on the recoil shield either. Hints on where to look and what to look for would be welcome. At this point I have not touched the revolver since the class and I need to clean it and check on why it malfunctioned.