Is this a Model 1905 2nd Change?

[Bedrock]

I just picked up what I think is a Model 1905 2nd Change, but I am not sure. It is well worn, with maybe 15% of the original finish remaining. It has been in the family of a good friend for it's entire life, and I am pretty certain it is all original. The wear on all parts is the same. The serial number 140,9xx, which I think places it withing the serial range of the 2nd Change. The walnut grips are heavily worn, but are correct, with the flat top and no medallions. It has a 5" barrel with the 3-line patent dates on top of the barrel. The right side of the barrel is blank. The cylinder, and the back of the extracter have numbers matching the serial number. But I am curious, because the extractor does not have the twin dowel pins. The S&W book says that the 2nd Change "generally" has the twin dowels.

Is this revolver a 2nd Change? is there another way to externally determine the difference between a 1st or 2nd Change other than the twin dowels?

Thanks in advance for any information you might be able to provide.

 

[DCWilson]

The first change/second change distinction is one of those things that should be simpler than it is. Based on the lack of dowels in the ejector star, yours would be considered a first change revolver. But if you pull the sideplate and look at the trigger rebound slide, there are other distinctions to be drawn. In the first change design, the rebound slide has a key on the backside that runs in a small slot milled into the frame. On the second change, that key and slot are removed. Also, the second change rebound slide is said to have a 1906 patent date stamped on it. I would have thought the first change slide would be similarly marked, but I guess not.

Here's a photo showing the slide key and slot on a 1905/first. In case that image is perplexing, the slide has been rotated up to show the key on the back side, and is therefore upside down. The ends of the slide are still in their proper left/right orientation.

If I had the authority to call the details of the first change/second change distinction, I would base it entirely on the keyed slide, and then recognize the presence or absence of dowels in the ejector star as "varieties" within each change.

 

[Bedrock]

Thank you very much for the explanation, and photo. I guess I will have to take off the side plate and check to see if the slide is keyed. Until I get up the nerve to do that I will consider it a 1st Change.

Thanks again.