I have for sale a blued Ruger Single Six with a .22lr cylinder only.
Guy who wants to buy it has one with a shorter barrel but with a .22lr and a .22 mag cylinder. Could he use the .22 mag cylinder in mine?
Can they be switched from one gun to another?
There is a reason that Ruger pairs the cylinders to a particular frame and numbers all three pieces. They were chosen at the factory to match up and interchange with proper chamber to barrel alignment.
The cylinders aren't hand-fitted to a particular frame, but they do select a close matching pair of cylinders and then fit the hand and bolt to both cylinders.
Due to manufacturing tolerences on both the cylinders, the frame, and the bolt and hand on the frame you can run into timing problems when you start swapping un-matched cylinders between frames. The chambers might line up with the forcing cone and barrel or they might be off one direction or another. that can mess with the accuracy of even cause some nasty splashback out of the barrel gap when using the mis-matched cylinder.
I have never seen that bad of an example from a Ruger convertible, but I have seen a lot of H&R convertibles that were offset enough that they wouldn't group at all even at 15ft.