645?

[Rusty Bob]

I have a S&W marked Model 645 that has factoory adjustable sights and I read that some early 4506's were marked as 645's, how can I tell? The serial number is TBK6XXX if this helps. Any information would be appreciated concerning date of manufacture.

 

[4T5GUY]

I have a S&W marked Model 645 that has factoory adjustable sights and I read that some early 4506's were marked as 645's, how can I tell?

Grips.

645 has two piece grips w/grip insert. 4506 has one piece Delrin grip.

645 front sight is integral to the slide. 4506 front sight is separate set in a dovetail in the slide.

The transitionals I’ve seen have the 4506 frame not the 645 frame.

1987-88 for dating.
Edit for clarification that the early 4506’s still had the step frame

Jim

 

[Sevens]

I read that some early 4506's were marked as 645's

When S&W implemented the “automatic improvement program”, their own name hatched for the debut of the 3rd Gen evolution, there were a number of things all going on at once.

There were definitely some models that appear to be almost a mix of 2nd and 3rd Gen. As said above, you would see a 2nd Gen model name stamped on the frame but you had the brand new 3rd Gen one-piece grip. For these guns, if you have the original box with intact end label, you’ll see a 4-digit number for the model rather than the 3-digit that was typical on every 2nd Gen.

Interestingly enough… this early 4-digit number did NOT jive with the eventual model numbers S&W devised for 3rd Gen pistols.

An early 4506 with a 645 on the frame but a one-piece grip would typically show a 6450 as the model name stamped on the end label. But I’ve also seen variations on this… certainly with other model, such as the 659 and 459.

Any confusion? Yes! And then there are the AIP-prefix pistols and the RSR-prefix pistols and the early 3rd Gen pistols that made use of what are obviously 2nd Gen parts, easily seen by the different finish and stamping style/font.

That last bit is near and dear to me as I am fortunate to have two different 3906’s and when I say different, I sure mean it! One of them looks like a 2nd Gen with a 3rd Gen grip & sights while the other one looks like a typical 3rd Gen.

—WHY— ?! We’ve long had a saying in S&W circles… “never say never” with S&W and also that S&W never (ever!) let anything go to waste. So many of the very earliest 3rd Gen pistols are modified 2nd Gen parts with the new improved features specific to 3rd Gens.

Makes for a lot of interesting discussion and enjoyable oddities to chase and collect.