Smith & Wesson K-Prefix Serial Numbers

What Are K-Prefix Serial Numbers?

Smith & Wesson used the K-prefix serial sequence on many postwar K-frame revolvers. These guns include important target, combat, and adjustable-sight revolvers such as the K-22, K-32, K-38, Combat Masterpiece, Combat Magnum, and later model-numbered variants.

The K-prefix itself does not identify one exact model. It identifies a serial-number family. To narrow the exact firearm, compare the serial result with the revolver’s caliber, barrel markings, barrel length, sights, finish, stocks, frame features, and model stamp when present.

Common K-Prefix Models

The postwar K-prefix range is associated with several Smith & Wesson K-frame target and adjustable-sight revolvers, including Models 14, 15, 16, 17, 18, 19, 48, 53, 66, 67, and 68, along with their pre-model variations.

• K-22 / Model 17
  A .22 Long Rifle K-frame target revolver. Early postwar examples are often called pre-Model 17 revolvers.
• K-22 Combat Masterpiece / Model 18
  A .22 Long Rifle K-frame with a shorter barrel and combat-style configuration.
• K-38 Target Masterpiece / Model 14
  A .38 Special target revolver and one of the classic postwar K-frame target models.
• K-38 Combat Masterpiece / Model 15
  A .38 Special combat-style adjustable-sight K-frame.
• K-32 / Model 16
  A .32 caliber K-frame target revolver.
• .357 Combat Magnum / Model 19
  A .357 Magnum K-frame revolver introduced before model numbers were stamped.

K-Prefix Serial Number Quick Reference

The table below is a collector quick-reference guide. It gives estimated production periods only. Smith & Wesson firearms were not always assembled or shipped in exact serial-number order.

K-Prefix Does Not Always Mean K-22

A common mistake is assuming every K-prefix Smith & Wesson is a K-22. That is not correct. The K-prefix range was used across multiple K-frame models and chamberings.

For example, a postwar K-22 may have a K-prefix serial number, but a K-prefix serial number alone does not prove that the revolver is a K-22. A K-prefix serial number could also belong to another K-frame model such as a K-38, Combat Masterpiece, Combat Magnum, or related model-numbered revolver.

Prewar K-22 vs. Postwar K-Prefix

The prewar K-22 Outdoorsman and early K-22 Masterpiece used number-only serial ranges. Those are different from the postwar K-prefix sequence.

• Prewar K-22 Outdoorsman
  1931-1940, serial range 632132-682419.
• Prewar K-22 Masterpiece
  1940-1941, serial range 682420-696952.
• Postwar K-22 / pre-Model 17 / Model 17
  Uses the broader K-prefix postwar K-frame sequence.

On the Serial Number Lookup, use Prewar K-22 — no K prefix, 1931–1941 only for number-only prewar K-22 serials. Use K-prefix postwar K-frames for serials beginning with the letter K.

How to Use a K-Prefix Result

A K-prefix result should be treated as a research starting point. It can estimate a production period, but it cannot confirm the exact shipping date or original configuration.

• Check the serial number carefully, including the K prefix.
• Compare the caliber marking on the barrel.
• Measure the barrel length.
• Check whether the sights match the suspected model.
• Look for a model stamp inside the yoke cut on later revolvers.
• Compare stocks, finish, and other features with known examples.

Example Searches

These examples show how the K-prefix lookup should be used:

• K13026
  Falls within the 1947 K-prefix range K615-K18731.
• K123456
  Falls within the 1951 K-prefix range K104048-K136690.
• K350000
  Falls within the 1958 K-prefix range K317823-K350547.

Try your own serial number in the Serial Number Lookup.

When to Order a Factory Letter

A factory letter is worthwhile when original shipment details matter. The serial-number range may estimate when a revolver was produced, but a factory letter may document the original shipping date, destination, barrel length, finish, stocks, and configuration when surviving records are available.

This is especially useful for uncommon barrel lengths, unusual finishes, historically interesting shipments, boxed collector pieces, or firearms with features that do not match the expected configuration.

Learn more on the Factory Letters page.

Research Notice

Seeing the Elephant provides independent collector research and estimated serial-number context. It is not affiliated with Smith & Wesson and does not replace official factory records. Serial-number results should not be used as proof of model, originality, condition, value, or exact shipment date.