- Remember that there is a flash gap between the front of the cylinder and the forcing cone or back of the barrel. That flash gap, as small as it is, permits a great deal of powder and metal bits to be sprayed laterally to either side of the revolver when it's fired. Anyone or anything on line with that flash gap will get sprayed with these small projectiles and injuries have occurred.
- The cylinder seems to be the most sensitive area for cleaning and maintenance. Make sure that no bits of grit or unburned powder are under the ejector star and that the ejector rod is tight. I had an ejector rod loosen on me once and I couldn't unlock the cylinder to reload. Hobby grade Loctite® is handy in keeping this from happening.
All in all, the S&W Model 64 still makes a good off-duty or field gun. Be realistic of what you expect to stop with it. Understand the six-round capacity. Practice with it so that you know what the point-of-aim/point-of-impact relationship is. The sights aren't adjustable. In fact, the rear sight is a groove milled into the top of the revolver or the "top strap."
I'm familiar with surplus Smith & Wesson Model 64 revolvers that are still in use twenty years after having been retired from a police department. They are properly maintained and function fine. They can make a fine secondary gun and should be available in surplus still at very reasonable prices.