So I am at the range yesterday and brought out the 4" S&W 500 for the first time in months. First 5 rounds go perfectly. Reload the cylinder and fire one shot then nothing on the second round. I leave the gun pointed downrange for a good 30 seconds to make sure it wasn't a delayed primer. After the time passed, I almost made a mistake that probably would have cost me dearly. I almost shot another round without checking. As I am still holding the revolver downrange I think better of it since the noise it made was slightly louder than just the hammer falling. The round was not a dud. It ended up being a squib. The bullet was lodged about 1/8" down the barrel. I do not even want to imagine what would have happened had I pulled the trigger again without looking. Thank God for common sense. This was the first squib I have ever had and of course it is in the biggest handgun imaginable. It took about 10 minutes to dislodge it from the barrel. At this point, I decided to just put it away and finish running my 1911 and XDs. Ended up being a good range day rather than a trip to the hospital. On the upside, now I know what a squib sounds like and will never almost make that mistake again.