Ruger1228:
I'll do my best. The S&W Model 41. .22 Rimfire Single Action Target Pistol was introduced in 1957 at serial number 1401 and shared the serial range with the other semi-auto pistols. By 1971 the serial range had reached 115000. The other models will help refine the date range down.
.22 short Model 41-1 introduced in 1960 around serial range 20000.
Model 52A for the Army Marksman unit shipped 1961-1964 in the serial range 35850 to 35927. These were effectively custom pistols, so I'm guessing all frames were 1961 manufacture then assembly as requested.
The Model 52 was produced 1961-1963, starting at serial number 50,000 with 3500 produced.
The Model 39 with steel frame and slide was shipped from 1966, some serial numbers between 1000 & 2600 (produced in 1950s but not shipped), some serial numbers around 39000 then more in the 60000 to 64000 range, then again in the 81000-82000 range.
The SCSW doesn't specify if the 81000-82000 range shipped in 1966, but i am inclined to think they did, otherwise production would have been less than 10,000 semi autos in all models for three years.
So, working off the above, I'm guesstimating that your gun falls into the period 1966-1971, serial range 81000 to 115000, average production of around 7000, guns a year, so 1966-8 with 1967 being most likely for your gun.
I'm sorry I can't do better than that, but I'm cheaper than a factory letter!
boricua9mm:
No need for pics, your Model 686 Distinguished Combat Magnum was manufactured in late 1982. There is a recall on this model, with some guns there is a chance of magnum primers flowing back around the firing pin into the firing pin bushing and locking up the gun. Under the recall S&W will pay shipping both ways and install a new pin and bushing. If it has already been modified there will be an M stamped near the model number under the cylinder yoke cut out.
your Model 686 CS1 for the US Customs service was produced in 1988 and is rather collectable.