Automatic K-304
1960 · 10k Solid Yellow Gold · Automatic
About the Automatic K-304
Made only in 1960, the Automatic K-304 appeared in a single catalog year as part of Hamilton's Automatic family. It runs on the caliber 661, a 17-jewel automatic movement, and came housed in a 10K yellow gold case with a white dial featuring embossed gold numerals and markers. The numerals and markers run only from 6 to 12, giving the dial a clean, asymmetrical layout that pairs with sweep seconds and Silhouette hands whose undersides carry luminous material.
Finding one with an undamaged dial is the real challenge here. The Silhouette hands sit close to the dial surface, and over the decades that proximity has left burn marks on more than a few examples. A clean white dial with no discoloration under the hands is something to genuinely appreciate when you come across it. The embossed gold numerals and the pearled track add tactile detail that photographs rarely capture as well as they deserve.
From the Catalog
Hamilton listed the K-304 at $150.00 in 1960 on a strap, describing the dial as featuring 14K gold numerals, markers, and dots with a pearled track, and noting the Silhouette hands carried luminous material on their undersides. The watch was also listed as weatherproof, a designation Hamilton used for its sealed cases at the time.
Hamilton Catalog Images
1960
What to Look For
| Dial | Look carefully under and around the hands for heat or contact marks. The Silhouette hand design runs close to the dial, and burning or discoloration in that zone is common. A clean, evenly white dial with no marks under the hour and minute hands is a meaningful condition point on this model. |
| Crystal | Check for chips, deep scratches, or crazing. A replacement crystal is far preferable to a cracked original, but confirm the fit is correct and the crystal sits flush without separation at the edges. |
| Movement | The caliber 661 is an automatic and should wind from wrist motion. A watch running on dried-out original lubricants can generate enough friction to stop completely, so ask whether the movement has been recently serviced. A watch that needs constant hand-winding to keep running is telling you the rotor or mainspring system needs attention. |
| Case | This case opens through the crystal side, not the case back. Look at the case back for pry marks or gouges from previous attempts to open it incorrectly. The 10K gold case can also show wear through to base metal at high-contact areas like the lugs, so inspect those spots in good light. |
| Crown | The watch was rated weatherproof originally, but that rating should not be trusted on a 60-plus-year-old watch. Make sure the crown screws down or seats properly and shows no corrosion. A damaged or loose crown is an easy water intrusion point. |
The Movement
The caliber 661 is a 17-jewel automatic movement made by Hamilton. It winds itself through an oscillating weight that rotates with wrist motion, so under normal wearing conditions it should not need manual winding. It is a compact automatic caliber suited to the dress watch proportions of this case, and like all movements of this era it benefits considerably from fresh lubricants.