What is the consensus of which is a better all around weapon. Specifically shootability and reliability / longevity.

I dont own too many autos, and no S&W autos. Just a couple glocks, a SIG P220 and a couple 1911's.

Both are very well built and reliable handguns. The 4506-1 is built on a stronger frame and platform and this was due to the Introduction of the 1006. The 10mm required a stronger frame and to streamline production Smith started building both handguns from the same platform and this is how the 4506-1 was born. There is nothing at all wrong with the 645 and 4506 no dash models, they hold up perfectly fine to 45 ACP.

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Go Big Blue

The 645 was more or less a 2nd gen "transitional" model.

I know some guys that still own and shoot 645's, and they have no complaints with them.

If I had to choose between a 645 and a 4506, though, I'd go with the 4506 for the improvements incorporated within the 3rd gen guns.

The 645's are interesting examples from an earlier time when S&W engineers were looking toward the future.

Having examples of both would make many S&W enthusiasts very happy.

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Ret LE Firearms inst & armorer

I'll vote for the 645, simply because I own one, and don't own a 4506 (yet). That said, I also love shooting my 4566 as well.

hang on...i'll look what's in the safe...

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SWCA#2208
KK4EMO

I prefer my 645 over all of the 4506's that have passed through my hand, although the last two were excellent shooters. One is for sale right now.

I vote 645 for two reasons, one grips choices are better.
Another thing I like is that I have had several with a red ramp sights and I do not remember any third gen guns that came with them.

Tough choice.........I own and like examples of both. They are similar, but have some distinct differences.

The 645 is slightly lighter than my 4506-1's. Perhaps slightly thinner as well.......I haven't put calipers on them.

The 645 had a very nice grip frame with the capability to use different grip panels. I like the Pachmayrs on it. I do wish the 645 had the undercut trigger guard like the 4506 as it lets the pistol sit a little lower in the hand.

The 4506-1 has a better trigger than the 645. Although I'm told that Novak's will put a very nice trigger on the 645 and undercut the trigger guard as well.

Reliability and accuracy are a wash. Both are bet your life reliable and tack driving accurate.

I like the look of the adjustable sight 4506-1 and I like the 645 with Novak sights just as much. So........I guess I'm no help to you at all.

The 645 was made for a shorter period of time and in fewer numbers than the 4506. So if there is a 645 in front of you, I would advise you buy it..........first. Regards 18DAI

Even though they both have the same grip, the 4506-1 still feels a bit fatter to me. The 4506 no dash is probably the slimmest gun I own, feels much thinner than my stock G.I. style 1911. I would love a 645 to add to the collection, but they are a bit wider than the 4506's, as they have grip panels vs. a wrap-around plastic grip.

I will agree with 18DAI on the trigger though, my 4506-1 has a much better trigger than both my 1006 and 4506 no dash, maybe it has to do with the non-chrome finished trigger and hammer? It's not MIM like the later models, but simply a black version of the old style trigger and hammer.