Are you mechanically inclined? Do you want a project? Do you have hollow ground gunsmith screwdrivers that exactly fit the screws? If the answers to all of these are "yes," then you might want to do it.
But under most circumstances, I tell people to let a gunsmith do "easy" repairs inside a S&W revolver. There is lots of advice on the internet that people should do simple repairs themselves, but actually, revolvers are deceptively not as simple as they look. And when a revolver needs a repair inside the sideplate, generally, all of the internals should be carefully inspected at the same time. An experienced gunsmith can do this inspection in only slightly more time than the disassemble and reassemble process and may not even mention it.
Also, needing to replace the cylinder stop spring is slightly unusual. It is certainly a part that occasionally does wear out, but not that often. So this definitely seems like a good time to have an experienced eye look everything over.
And if you were wondering, yes I do work in the inside of revolvers. Here is an article I wrote after I spent a lot of time thinking about double action trigger pull.
Table of Contents 1. Part One: General Concepts 1.1. Introduction 1.1.1. Disclaimer 1.1.2. The author is not compensated for endors...
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