I bought my S&W model 10 in the summer of '86 from the NYPD equipment section, I regularly cleaned it, but it was a working gun, I bent the extractor rod, knocked it out of time and had a full lock up failure. It was no fault of the gun, my model 10 was a victim of circumstances. The gun was retired by me after 5 years when NYPD went to the Glock 19. Revolvers do fail, the more you use them, the more you abuse them, the faster it will happen. Regular services and cleaning goes a long way, but every thing has it's limits. There was a guy in my precinct that had so much jelly donut jelly and fried onions on his revolver when he pulled it out at the range, that they had to give him a loaner to qualify while the range staff soaked and cleaned his. Keep them clean, your life may depend on it.