Jeff,
Here are the 6 (or 7 on TLs) fixed sight frame serial # locations pre war and locations remaining after WW II until 1957 to look for (not including pre war target sight stamped serial #s):
Gun butt - or forestrap on I frames with grips that cover the butt
Barrel - bottom of barrel or in extractor shroud
Yoke - on rear face visible thru a chamber with a flashlight
Extractor star - backside
Cylinder - rear face
Right stock* – depending on vintage, stamped, scratched or penciled on backside of original grips
Mid-lock cam plate –.44 HE 1st Models only (up to all 5 digits).
*Stamped since 1857, stock #s, always right side only, changed to penciled #s c. 1900 and back to stamped #s in 1929. Scratched, penciled or stamped on hard rubber grips; finally discontinued ~ late 1970s.
Assembly (factory work) #s: Other multi-digit numbers of 3 to 5 digits, are on the yoke at the hinge, in the 'yoke cut' on frame opposite the yoke near the hinge, and inside of the sideplate, for the pre war and early post war period. The assembly # in the yoke cut of the frame was relocated to the left side of grip frame after model #s were assigned and the serial # was added in the 'yoke cut' where the assembly #, moved to the grip frame, used to be. You know they are assembly (factory work) #s because of those 3 locations that always match on guns that are original, and that's the only usefulness for them after guns leave the factory: still used to this day, long after serial number locations decreased.
Here's the story of the production process including when and how the 'work numbers' are used in brief from 'the man' himself:
"I will give you a general outline of the manufacturing process up to about the 1957 period when the soft fitting department was eliminated. The company is divided into departments, forging, frame, barrel, cylinder, small parts, heat treat, stocking department, soft fitting, polishing, finishing, hard fitting, test range, final inspection, and shipping. The flow is roughly in that order.
"Bar stock is forged into frames, barrels, hammers, triggers, and side plates stamped from flat stock. These parts are all trimmed and sent to the appropriate department. In each department the parts are machined to a finished stage.
"In the frame department once the frame is partly finished a yoke is fit to it and the yoke and frame are stamped with a work number. The frame is then sent to the man who fits the side plate which is swaged onto the frame and the side plate is given the work number in the slot cut for the hand. The yoke and side plate are over size so the frame with these parts in position are sent through the machining operations so that they are blended together.
"When the frame is finished it is sent to the stocking department where a pair of stocks are fit to the frame. Once the stocks have been fit, the frame, yoke and the stocks are stamped with a serial number. Only the frame will have a letter prefix if one is assigned to that model. The frame is then sent to soft fitting and the stocks to finishing and when they are done to the inspection department.
"In soft fitting the frame is fit with a finished barrel, cylinder, and internal parts. The barrel, cylinder and extractor star are stamped with a serial number. The gun is disassembled and the small parts placed in a bin and sent to hard fitting. The frame, barrel, and cylinder are sent to polishing then to get a blue or nickel finish.
"Once completely finished they are sent to hard fitting, where the gun is assembled, the fitter stamps his mark in the yoke cut, and its inspected by the floor inspector. From hard fitting the handgun goes to the range where it is test fired and marked with a prick punch mark in the lower front corner of the cyl window, usually.
"From the range it goes to the inspection department where the first inspector finds the right numbered pair of grips and puts them on the handgun. It then goes to final inspection where all the features are inspected for proper function. Then it is packaged and moved into the vault. From there it goes to the distributor."
Roy G. Jinks
Historian, Smith & Wesson
NOTE: Once soft fitting was eliminated as of May 1, 1957, serial numbering of the yoke, cylinder and barrel were no longer needed to insure all the matching 'soft fitted' parts got back together and were also eliminated.
).
