I attempted to install the factory weight on my 52-2, but it would slide out of place when fired. I only tried to secure it a few times, and noticed it had marred the underside of the frame as it came loose. Fortunately, that damage isn't visible with the weight installed. I was lucky enough to find a nice gunsmith at the S&W warranty repair facility who did it for free while I waited-- it only took him a few minutes. He said the trick was to put a piece of lead shot in the indentation, and then tighten the screws to the frame -- have left the weight installed, and it has worked like a charm for 20 years.