OK guys, I'm baffled. I have a Model of 1955 that I use to dispose of reloads that my National Match doesn't like. Problem is that I don't have a manual for it. So here's my question. There is a screw in the front of the trigger guard just below the barrel. What does it do? I really don't want to mess with it without some idea of what it's for. Help?

No need to mess with it. It holds a spring in place.

I believe it's the cylinder stop spring.

It is called the cylinder stop plunger screw. The screw was eliminated via a change order issued in November 1961 implementing the new cylinder stop; resulting in 3-screw revolvers being shipped in 1962.

Why would you want to mess with it?

Bill

This is absolutely the right question. Unless, for some strange reason, you need to completely disassemble the revolver, there is absolutely no reason to remove the cylinder stop plunger retaining screw. I guess the only other reason would be if something is wrong with the cylinder stop and it needs to be replaced.
Just leave it be and shoot your revolver. That's my advice.

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Jack
SWCA #2475, SWHF #318

Thanks all. Advice taken.

When a S&W is referred to as a 5-screw (or later, a 4-screw), the plunger screw counts as one of them, when present. Four (or later three) screws hold the sideplate on. The hammer spring tensioning screw is not counted.

I have such a twisted mind.

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Oh well, what the hell.

Yea, me too.
I immediately went back to my college days when I read the title of this post.

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Thugs that comply don’t die!

Mystery is a good word