What is wrong, and how do I fix it.  The cylinder is loose, and if I remove the round ejection rod it slides easily off of the shaft that retains the cylinder.  It would seem that something should retain the cylinder?  I do not see anything to do that.  
  It will rotate and fire every round, when loaded.  It is annoying that when I go to eject the empty shells, the whole cylinder moves.  If I hold the cylinder the shells eject fine, but this should not be.
  Really like the gun.  Very accurate and fun to shoot.  I bought the gun about 5 years ago used.  Just started to have this problem.  
It is a 357 Mag with the 2", 4" and 6" barrels.