Post Fri Mar 31, 2023 1:46 am

Sargent 5 pin question

Hello everyone,

I have noticed on older Sargent 5 pin factory keys, sometimes the bitting stamped has 5 digits (expected) but with an added X at the end (like 38765X). These keys have a 0 cut in the sixth position, and it is cut on a regular 5 pin blank, the 6th cut being on the very tip. I assume the cylinders are pinned with a 0 pin in the 6th chamber, but I have never disassembled one. What is the function of this? I have also rarely seen some 6 pin keys that have the X in the 7th position.

I have also read in the CR cylinder manual that some old Russwin keys had a "guard pin" in the 6th chamber and I believe it was a 6 cut on the tip of a 5 pin key. The manual does not elaborate on this, however.

Many thanks.