−27%
Palmetto State Armory
Glock 19 Gen5 MOS
$549.99
$399.99
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Why two sources give two different years
You looked up your serial number in two places and got two answers. That is not a sign that one of them is broken. It is the single most common thing that happens when a firearm is dated, and it usually means both sources are behaving exactly as designed.
The community working this out in public put it in five words: two sources in disagreement means no source. A tool that returns one confident year and says nothing else is not more helpful than a forum thread — it is less, because the thread at least shows you that it is guessing. This page set explains what actually produces the discrepancy, and what to do instead of picking a number.
Where this site stands. Our serial lookup already refuses to guess: where a number sits between published ranges it reports the range, never a single year, and it shows the threshold behind every result. This page set is that principle made explicit — it names the causes, including the ones that make our own coverage look thin.
Six documented reasons it happens
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The table and the gun disagreeTwo dating systems on one firearm record two different dates, and both were put there by the factory.Read this cause →
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The published table is known to be impreciseSometimes the two answers come from the same table read two ways — and sometimes the table is simply known to be off.Read this cause →
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The maker’s own lookup returns two yearsAnd does not say why. This is the case that sends people to a forum to ask whether their gun was made twice.Read this cause →
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The numbers are not in the order you assumeThe assumption underneath every serial table — that lower numbers are older — is false for more makers than people expect.Read this cause →
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There is nothing left to checkWhere the factory ledgers were destroyed, every year you can find online traces back to somebody’s reconstruction — and to nobody’s record.Read this cause →
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The number on the gun is not the original oneImporters renumbered, arsenals renumbered, and some numbers had to be transliterated rather than copied — so the number can be real, recorded, and still not match any chart.Read this cause →
Why this page exists rather than an apology. Every other dating resource on the internet hides this. It gives you a year and moves on, because a year is what the reader asked for and uncertainty is a harder thing to sell. The consequence is that people find out later — on a forum, or from a buyer — that the number they were given was one of two, and there was no way to know.
A competitor with more serial ranges than us cannot copy this page by adding more data. Counting ranges is easy. Saying what each range is worth, and where the source itself admits it is imprecise, is a different job — and it is the one that makes a dating tool worth trusting.
See it on a real number
The lookup shows the published threshold behind every result, and where a maker's table is documented as imprecise it says so on the result rather than returning a bare year.
Open the serial number lookup Who holds the recordsSix causes, each sourced to a named document or specialist account, compiled and last checked 2026-10-14. Where the evidence does not support a cause, it is not listed here.