I'll try to ask this question without catching the obvious heat and response of "don't do it". Been searching the forums for info on a 649-4 I have, but not much out there that seems to address my question. My 649 has the 2.16" barrel and is stamped .38 S. & W. SPL. Serial # CCD47xx. However, the cylinder chambers 357 mag and closes with more than sufficient space to close the cylinder. The guy that owned the pistol before me said he routinely shot 357 mag in it. He says he contacted S&W about the cylinder/barrel/model questions and said they agreed he could shoot 357 mag if the round would fit. Does this story make sense and does anyone else have a 649-4 with a cylinder that will close with a 357 mag chambered? Also, first post. Thanks for any feedback.