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Hamilton Grade 940 Pocket Watch Identification & Technical Specs
Guild Home > Archive > Hamilton Grade 940 Pocket Watch Identification & Technical Specs

Serial Number & Production Dating Lookup

Enter the 5 to 8 digit serial number stamped directly on the movement plate (not the watch case):

AMERICAN WATCHMAKER • American Watchmaker Hamilton Grade 940 DIAMETER: 42.4 mm | JEWELS: 21 Jewels | FREQ: 18,000 BPH ARCHIVE SPEC
Original Horological Blueprint • American Watchmaker Hamilton Grade 940 Movement Architecture

Technical Specifications & Factory Archival Records

Grade / ReferenceGrade 940
Movement Size18s
Jewel Count21 Jewels
Railroad Certification✓ Certified Railroad Grade
Vibrations Per Hour18,000 BPH (2.5 Hz)
Balance Lift Angle50°
Power Reserve36 hours
Escapement TypeStraight line lever escapement
Balance Wheel ConstructionExpansion balance
Hairspring SpecificationBlued steel Breguet spring
Shock Protection SystemRigid balance jewels

Horological Architecture & Collector Notes

The American Grade 940 was engineered to meet rigorous American horological standards during the turn of the 20th century. Utilizing high-grade alloy components, a precision Straight line lever escapement, and 21 jewels with fine ruby endstones, this movement provided exceptional isochronism and positional stability.

Among vintage restorers and conversion specialists, this series is admired for its accessible gear train geometry and solid metallurgy, making surviving specimens excellent candidates for preservation and custom recasing.

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