Inspired by Allen-frames iconic Ultimate Highway Patrolman thread and the wealth of information we have all gained from it, I would like to see if we can learn a little more about the Combat Magnum and the changes made to it over the years.

As with the threads on the Highway Patrolman, there are many threads on this forum containing info on the Model 19 and 66 Combat Magnums. Trying to find the bits of information hidden within them all would be very time consuming and might still lack some bit of information that could shed some light on these for the rest of us. So, the more information pertaining to the engineering changes we put here, the clearer the picture may become.

It has been well published that the engineering changes are as follows:

“pre”...............(1955) Thanks to S&W and Bill Jordan, introduced at K260001
19..................(1957) Stamping of model number
19-1...............(1959) Change extractor rod, right to left hand thread
19-2...............(1961) Delete trigger guard screw, change cylinder stop
.....................(1963) 50 made with 2-1/2” barrel; K544672-K544721
.....................(1966) 2-1/2” barrel introduced as standard
19-3...............(1967) Relocate rear sight leaf screw
66..................(1970) Introduced at K949100
19-4 (66-1)......(1977) Move gas ring from yoke to cylinder
19-5 (66-2)......(1982) Eliminate cylinder counterbore and pinned barrel
66-3...............(1986) New yoke screw, floating hand, and hammer nose bushing
19-6...............(1988) New yoke screw, floating hand, and hammer nose bushing
19-7 (66-4)......(1994) New rear leaf sight, drill and tap frame, change extractor, and Uncle Mike’s synthetic grips.
.....................(1995) Delete square butt
.....................(1997) Change to MIM thumbpiece and trigger
19-8 (66-5).....(1998) Sep – Change to MIM hammer and floating firing pin
.....................(1999) Discontinue 2-1/2” barrel
.....................(1999) Nov – Model 19 discontinued
66-6...............(2002) Introduction of the Internal Lock
.....................(2005) Model 66 discontinued

If you were to go back and look at some of my old threads, you’d see I was quite confused about the Model 19, and it was the reason I joined this forum.

For example, the change from the -2 to the -3 was the relocation of the rear leaf screw. At the time I had a -2 (K7952xx) that not only did it ship in late 1968 (-3 announced in 1967), I could see no difference in the sight screw between it and the later ones I had. No wonder I was confused.



It wasn’t until recently when I picked up an earlier -2 (not much, Jun-68) that I noticed that its rear leaf screw was located further back, right over the barrel/cylinder gap.



So, they are both “-2” but K7952xx appears to have the “-3” engineering change. My hope with this thread is that we can narrow down where that and some of the other changes occurred.

As I am sure we have all noticed, serial numbers vs. time frame seldom matter with S&W. Although I have seen non-model marked Combat Magnums in the K38xxxx range, here’s a 4-screw Model (marked) 19, K3166xx.



It’s not like we need an excuse for a picture thread here but maybe a closer examination of the Combat Magnums we own can bring some interesting and informative facts about them to light.
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1/1/12
Here's a third version of the chart I am working on showing which model and serial number range. It is a work in progress! I will update it as I go and let you know if something significant changes.

Click on the picture for the full size image (thumbnail is more updated than link, for now.)