I'm sure this has been asked and answered in pieces but I keep searching and seeing maybe conflicting info. Apologize for bringing it up again. Assumptions:

Slides are either blued carbon steel or stainless steel

Frames are either aluminum with a black or stainless finish or carbon steel with a blued or stainless finish? Or are the "stainless" steel frames actually stainless steel and the blue (black) are carbon steel?

I ask this because I seem to see a difference in frame colors or sheen on different models. Maybe there's not a universal answer. Further confused because my 2nd gen 645 is stainless frame and slide. Were stainless frames dropped in 3rd gen?

Lastly, is there any reason to not buy a nice 3rd gen with flash chromed trigger/hammer parts? I have a few nice examples with MIM parts as I have read they are superior in trigger break but I don't see a reason not to buy at least one of everything. And if I'm shooting bullseye I'm probably going to shoot something a bit more exotic or my Model 14 SAO anyway.

Thanks for your input!

Black frames are anodized aluminum (models ending in “4.” The 3rd generation exception off the top my head is the 4505.
Silver frames ending in 3 are anodized aluminum.
Silver frames ending in 6 are stainless with the exception being the 6906 series that have aluminum frames.

The 4th digit of the 3rd gen model number denotes frame material.

3 = aluminum frame with stainless slide
4 = aluminum frame with carbon steel slide
5 = carbon steel slide and frame
6 = stainless steel slide and frame
7 = carbon steel slide with stainless steel frame

Thanks for the quick replies. I have the chart from luckygunner but then there are the exceptions (like the 6906) that get me confused...guess I just need to buy one of everything and a magnet.

The 6906 and friends are a glaring departure from the rest of the 3rd Gen numbering system which the luckygunner chart will generally be accurate for. If named consistently the 6906 would be a '5913' denoting it as a short barrel compact aluminum frame variant of the 59-series like how the 3913 is to the 3906 what the 6906 is to the 5906, but S&W likely wanted a clear follow up to the 2nd Gen 4/5/669 so they just updated that. Stainless frames were still common and the 3rd Gen equivalent of your 645 would be the 4506. With MIM vs flash chromed parts my experience is the MIM parts are smoother and I've never heard about them breaking. The flash chroming looks nicer though.

No apology needed.

Questions are always welcome because that's how people learn.

This is correct.

Frames will be made of one of three materials:

Aluminum alloy with either black or silver anodizing. (Sometimes there are shade or hue variations among the silver anodized frames.)

Carbon steel with a black finish. (Not a lot of these produced.}

Stainless steel with a media tumbled matte finish.

No reason whatsoever.

In fact, most people like the look of the silver parts.

Some folks will even go so far as to replace the MIM hammer and trigger with the chromed components just for esthetic reasons.

It is true that the MIM hammer will typically provide a smoother double action trigger pull because the MIM hammer is usually smoother than the machined hammer where the sear drags across it during the double action pull, but a machined hammer can be smoothed in that area to provide as good a double action pull as the MIM hammer.

You're welcome!

John

Thank you all! So I just pulled a 5906 out of my safe that I "forgot" about. MIM parts, but it has a U stamped on the right side (shooters perspective) of the frame. Slide and frame finish match perfectly and they are mildly magnetic (stainless). Any idea what the U means? The dealer I bought it from said it was NOS.

So then I guess I "need" a 6906 little brother - smaller, lighter...

It has been repeated that a "U" stamped on the frame is an indication of a gun that was returned to S&W and then refurbished for sale.

Others have said it's just an inspector's mark.

I can verify neither.

John

Well someone should... and please post pics frequently so the rest of us can follow your progress (while sitting back with beer an popcorn).

Seriously, you have your work cut out for you, the combinations of 3rd gen guns, triggers, sights, magazines... are endless. Even Smith & Wesson catalog editors had to publish a chart for the "Understanding Third Generation Pistol Numbers"... and still left out a few details.

.

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Yes you do!

John

Well apparently the U means used as marked by S&W for a variety of reasons. Interesting. I can't see that it was ever fired or used. Maybe sold, shipped in place, then refunded and re-sold? There were a bunch of NOS released over the last year or two.

The "U" seems to have included samples and evaluation units that were returned to the factory. They couldn't be sold as new, so we're marked used and released for retail sale.

As to the 6906, it should have been the 6913, but someone at S&W didn't want to confuse chiefs or purchasing agents, so it was labeled the 6906 instead.

Chiefs and purchasing agents get confused easily, you know.

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Can open, worms everywhere.

Since my Chief is not on here, yes they do!

Wow.... and just like lanes and traffic signs in Italy, they are just a suggestion

Or speed limits in most of Texas.

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Can open, worms everywhere.

I blame the Marketing Department, not the Police Chief... That fold-out color chart I posted above is more confusing than the periodic table. No wonder they all started buying Glocks,

Yep, the 6906 ought to have been named a 6913 if they'd wanted to be consistent with how they'd properly named their 3913. The 6904 would've been a 6914 (like the 3914).

The 469/669 made more sense, in a way.

Never Say Never with the fanciful decisions made by them, though. Kept everyone guessing.

The 908 & 909?? Ask Carnac the Magnificent ...

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Ret LE Firearms inst & armorer

908 = 9mm Value Line Single Stack gun with 8 round magazine.
909 = 9mm Value Line Single Stack gun with 9 round magazine.
915 = 9mm Value Line Double Stack gun with 15 round magazine.
910 = 9mm Value Line Double Stack gun with stupid Clinton 10 round magazine, but oddly enough a 15 round magazine fits just fine thank you.

And so on. 457...

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Can open, worms everywhere.

Please don't start with the value lines, I'm trying to concentrate on spending money on all metal parts.

And we went from 17's to 22's and back to 17's. So I showed up for quals with a hi power. Chief looked at my target and just said "*******."

And thanks to this forum now I need a 457...

oops sorry for the language

And don't forget models like the 908 were available in both aluminium and stainless frames (908S)

And Chief's Specials like CS40 were also made in various finishes; black, natural, and two-tone

I need one one each CS9D, CS40D, CS45D in each finish.

[
No reason whatsoever.

In fact, most people like the look of the silver parts.

Some folks will even go so far as to replace the MIM hammer and trigger with the chromed components just for esthetic reasons.

It is true that the MIM hammer will typically provide a smoother double action trigger pull because the MIM hammer is usually smoother than the machined hammer where the sear drags across it during the double action pull, but a machined hammer can be smoothed in that area to provide as good a double action pull as the MIM hammer.



You're welcome!

John[/QUOTE]

Not all 3rd Gen guns have MIM parts, I have a NOS 4506 that has a build date of April 2000 that has non of the MIM parts from the factory. I believe it is a transition gun because it does not have the frame cut out above the trigger, I have seen this on other examples with the same serial prefix (TEU).

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That’s challenging. I’m 4/6 of the way there and stuck.

Not all 3rd Gen guns have MIM parts, I have a NOS 4506 that has a build date of April 2000 that has non of the MIM parts from the factory. I believe it is a transition gun because it does not have the frame cut out above the trigger, I have seen this on other examples with the same serial prefix (TEU).[/QUOTE]

Yes, it is well known that MIM parts didn't start showing up on 3rd gen pistols until circa 1994.

That configuration of frame and components makes me highly skeptical of April, 2000 production (possibly shipment?) but I never say never with S&W.

John

I need to maybe correct my build date to April 1990. Box reflects 0116. Does this sound right? I know it was a NOS gun, had not been fired, or if it had it only had a mag put through it. The Mags that came with the gun had never been loaded, and the spare was still in the paper. The breach face of the gun was spotless as well as other components in the gun. No slide wear marks at all. It was defiantly a rare find for a pistol of it's age.

April, 1990 feels right for that configuration, Dino.

John

Before I posted I should of done my homework, the pistol came with all the paperwork, tools, and cleaning kit, and the original box. My research shows that the transition gun is a little bit of a rare breed. Not having the frame cut, same frame as the 10mm and no MIM parts is a plus on desirability. My favorite in my collection is a Kimber Compact Custom, they only made just over 2000 of them with the configuration mine is in over a four year period. Never fired new in box. At the same time I bought it I purchased a Kimber Eclipse Target, the first series 70. New in box never fired. I shoot this one and it is a laser with the adjustable target sights. It is actually my favorite 1911 to shoot, as well as anyone who put it in their mits and shoots it, truly an amazing gun to shoot. And a couple of my friends are 1911 snobs owning high end EB's and DW's and other various makes not as common.

So how about the 4040? I think Franke N. Stien was in charge of naming the models.

Careful here… that frame was definitely NOT stainless, it was merely a silver colored aluminum alloy frame, like the 3913.

The "value line guns " are just as confusing as the mainstream models. The 908/909/910/410 all have plastic parts.
The 915/411 do NOT.....ALL METAL.

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S&W BG380, S&W 915 9mm

One reason I love my 4567. Limited production model from 1991, blue carbon steel slide, stainless frame, made pre-mim parts. And it's a ton of fun to shoot lol. Oh and factory night sights too (though these were recently refreshed by Trijicon ).