Home / Why two years? / The published table is known to be imprecise

The published table itself is documented as inaccurate

The published table is known to be imprecise

This is the case the corpus names directly, and it is uncomfortable because the imprecision is often acknowledged by the people who maintain the table.

A real case

From the record

On Winchester dating, the community’s own verdict is blunt: "Most of the numbers you will find online are erroneous (including the PDF on ‘Winchesters’ website.)" and the tables "can be off as much as 3-5 years".

What actually produces the discrepancy

A published serial table is a list of thresholds — the first number shipped in a given year — not a record of when any individual firearm was made. Between two thresholds sit thousands of firearms whose real dates are spread across the interval. A table with 3-5 years of documented spread is not lying; it is answering a coarser question than the reader is asking.

What to watch for

This cuts both ways, and it is worth saying: a table being imprecise does not make it useless, and it does not make a precise-looking competing table trustworthy. The competing table is usually a threshold list too — it just does not say so.

What to do about it

Working with this cause
  • Check whether the source is a threshold list or an individual record. The first gives a range by construction; only the second can give a date.
  • Where a spread is documented, carry it into your own notes. Writing "1928" when the table supports "1928 ±3-5 years" is the error that gets found out later.
  • Prefer a source that states its own limits over one that does not. A table that admits 3-5 years of spread is more useful than one that presents a single year, because you can price the uncertainty.
  • For a piece you intend to sell or insure, treat any table-derived year as an estimate and say so in writing.

Sources for this page: Cody Firearms Records Office — Winchester serial number ranges · National Rifle Association museum — on firearms that are hard to identify or value.

Other reasons two sources disagree

The table and the gun disagreeThe maker’s own lookup returns two yearsThe numbers are not in the order you assumeThere is nothing left to checkThe number on the gun is not the original one
The lookup shows its working

Every result names the chart it came from, the threshold it rests on, and — where the published table is documented as imprecise — says so on the result itself rather than returning a bare year.

Open the serial number lookup All the causes

Compiled and sources last checked 2026-10-14. This page explains a documented discrepancy; it does not date your firearm.