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Hamilton 505

Probable

Both a production caliber in its own right and the service replacement for the 500. Its dual role is why caliber and case date so often disagree on these watches, and why that disagreement is not a finding.

Specifications

Movement manufacturer
Hamilton
Production
1959–?
Winding
manual

Architecture

The revised electric caliber, with a reworked contact system addressing the 500's failure mode.

Related calibers

References using this caliber

Provenance of this record

Sources & Evidence

Secondary sourceCollector research

Hamilton collector research on the electric calibers, named models and case reproduction

Collector communities and specialist dealers

Accessed
2026-08-19

Cited for

This referenceProbable

Last verified: Not yet reviewed