No, it isn't normal to have any movement. The frame and barrel have been taken apart so many times that the fit is worn between them, and should be tightened. You can send the gun back to Ruger, and they will probably peen the stud in the grip frame that fits into the slot on the bottom of the barrel. That's exactly what they did to one of mine years ago. Alternatively, if you have a bit of mechanical skill, you can do it yourself. When putting the 2 back together, it should take a bit of pressure to force them together. This is good; there's no real reason to take the 2 apart on a Mark 2 for normal cleaning. I've peened 2 myself over the last 15 years or so. If you're reading this in disbelief, saying "what's he talking about?", send it back to Ruger.
