Any idea where this KMF-prefix 5906 came from?

[drumminor2nd]

Hey, all. My brother-in-law passed away last year, and as I'm the only "gun guy" in the family, the estate sent me his 5906 that I picked up today. The serial number is KMFxxxx, it has a "U" used stamp on the trigger guard and a "used" box end sticker. The box still has the 2002-dated CoBIS fired casing for a state database (he lived in Ohio, so he didn't need it) and a 10-round AWB-era magazine. If my research is correct, these markings and dates mean it is likely a police gun that sat on an armorer's shelf at a police department before getting traded back in to S&W. Does that sound about right?

And has anyone figured out the KMF prefix (not listed in the SCS&W 4th), and which department(s) might have had them? I heard something about Kansas City or Kansas state police, but I can't seem to find that information now.

 

[Sevens]

Most definitely a very oddball serial prefix — not just for a 5906 of that vintage, but it’s just not a typical serial prefix that S&W has used for anything mainstream.

I believe your theory about it being a run for a specific LE contract makes the most sense.

Other ideas that seem reasonable (if unlikely….?) is that it was a replacement frame made later than the pistol originally shipped. But this idea doesn’t make sense considering the box end label looks period-correct down to the wear and coloring on it.

The 6-digit product code has the leading “6” which is proper S&W-speak for “used gun” as it notes on the end label but it makes sense to mention exactly what constitutes a used gun in S&W factory speak.

It doesn’t mean that Billy Bob bought it at Gun ‘R Us and stuck it under the seat of his F-150. Rather it means that the factory took it back in to inventory and it could have been a contract over run, it could have been factory serviced from a large contract, it could have been a saleman’s sample gun, it could have spent time at a SHOT Show or similar industry or trade show, perhaps fondled by many or even used for live fire in some promotional event for the brand.

Oh man…
I have a friend that has a really crazy rare 1-of-1 S&W pistol and according to the box label, it too was a used gun. It was shipped to Jerry Miculek and eventually returned “to inventory.” I don’t know how he got it. It’s awesome. But it’s just another crazy example of what gets coded by the factory as a used gun.

Oh, actually I have one also, although it is a revolver. It appears as new in box and even shows evidence of the factory test fire and no other use… but wears the leading 6 product code and a secondary box end label over the original as a used gun. It’s a mint 16-4.

I would certainly send an e-mail to S&W with that serial number and 6-digit product code and see what kind of reply you get.

But — I would bet a crisp newone dollar bill that if you asked S&W once and then again at a later date… or if you e-mailed and then later called on the phone… you may very well get two different answers. And you would get a better answer with a factory letter, but that’s a $100 exercise, may be hard to justify.

 

[JRD]

From the roll stamped lettering, your gun is old enough to predate the laser marking era. Likely sometime early to mid-90’s at latest.
The fact that it has a 2002 dated test fire case shot by Gene Sypek says that it most likely came back to the factory as an LE used gun trade in, was inspected by a gunsmith, and test fired before it was sold as a used gun to a distributor. Gene Sypek is a now long retired performance center charge team gunsmith who could have inspected and test fired LE trade ins.

 

[ACEd]

I doubt the K indicates a state except for KSP (Kentucky State Patrol 4566TSW)

There were several 3rd generation Kxx prefixes observed as early as 1998 and as late as 2003. Most of which seem to have been made in the dates above but most of the 5906 & 5946 seem to have been Surplused from inventory and sold years later circa 2023 with end dates in January 2019.

KJF for 5943, 4006, 910 one with 8xxx box end code

KLB for 5946 & 4566

KLF for a 5946 believed to by a NYPD gun and 3x 5906 with a 108176U Product Code and a box end date 011119 thru 011419

KMF for 5906 with a 108176U Product Code and a box end date 011119 thru 011519 (5 observed) plus a single KMF19xx dated by SW as 9/1998

KNC for 5906 with a 108176U Product Code and a box end date 011519 thru 011919 (6 observed).

I purchased one of the KNC group in 2023 when there were several dealers selling large quantities of "Used" but actually surplus NOS 5906 & 5946 pistols most if not all with January 2019 box end dates. A couple of vendors let you select from 10 or more S/N incl the above Kxx prefixes and several Vxx prefixes - all sold under 108176U or 5946 under 108186U product codes. SW dated the manufacture of my KNC11xx as 7/1998 despite the 011119 box end date.

I have also seen 1x 5906 with 608176 code and 2x 5946 VJP35xx with 608186 codes and box Ends marked "Used". I have one of the 2023 surplus 5946 also VJP35xx but code 108186U and date code 011419 but checked by SW = Manufactured 5/2009.

 

[ACEd]

P.S. The Kansas City PD 4006 & 4026 had a logo on the slide - there was some discussion of that you may be thinking of but they were within common non-unique s/n prefixes

 

[drumminor2nd]

Thanks for the help so far! I emailed S&W last night, so I should have an answer in a couple of days.

Quick question: Does anyone have rough dates for when S&W moved to MIM parts and to the laser model/serial engravings? That should help me narrow it down some.

I need to detail strip it to clean it up inside, so I can catalog what all is MIM in there (trigger, hammer and sear are obvious from the outside and having the grip off to swap it for the NOS flat-backed grip I bought six months ago after I learned I'd be getting this). Did all the parts change at once, or was it over a period of time?

Also, any ideas on how to safely remove the second sticker from the box to see what's on the one under it? I can faintly see through the top label, and it appears to be a different set of markings underneath (and the serial number is on the bottom left of that sticker -- which matches the top sticker and gun). If I can get it off, that might reveal some more helpful clues.

 

[JohnHL]

A gentle application of a hair dryer can warm the label glue to allow removal.

John

 

[drumminor2nd]

Thanks. Tried that, got the two labels off together and took a photo with my phone of it from behind against a bright light and mirrored the image to read it. Turns out the first sticker is for a different gun about 1,000 serial numbers off but otherwise spec'ed the same way, so no real help for me.

Oh, well -- worth a shot. I'll put the stacked stickers back in the box and glue them back on some other time.

 

[drumminor2nd]

And you would get a better answer with a factory letter, but that’s a $100 exercise, may be hard to justify.

From the SWCA letter website: "PLEASE NOTE: At this time we are unable to letter Smith & Wesson firearms with “triple-alpha-numeric” serial numbers that date from 1982 to about 2013."

Had my $90 all set, too...

 

[Sevens]

I truly had no idea this was the case!