Seiko 6138-0040 Bullhead Chronograph Value Guide

The Seiko 6138-0040 Bullhead is a cult classic horological icon defined by its top-mounted crown and pushers that resemble a bull's horns. This Japanese-made automatic chronograph is highly collectible for its unique racing-inspired ergonomics and the sophisticated caliber 6138 movement featuring a column wheel and vertical clutch.

What affects the value of Seiko 6138-0040 Bullhead Chronograph?

• Condition of the original brown and gold color scheme, as aftermarket 'AM' dials significantly reduce market value.
• Mechanical functionality of the caliber 6138 movement, specifically the crisp reset of the chronograph hands.
• Presence of the original Seiko-signed stainless steel fishbone bracelet versus modern replacements.
• Overall case sharpness, as over-polishing can ruin the distinct 'Bullhead' geometry and lug definition.

How to Identify Seiko 6138-0040 Bullhead Chronograph?

• Verify the distinctive brown dial paired with gold sub-dials and the original 'Fishbone' stainless steel bracelet.
• Check for the 'Speed-Timer' or 'Chronograph' text on the dial which varies by regional market release.
• Ensure the case exhibits the correct asymmetrical thickness, being thicker at the top to accommodate the 12 o'clock pushers.
• Inspect the Hardlex crystal and the tachymeter bezel for authentic wear patterns consistent with 1970s materials.

History of Seiko 6138-0040 Bullhead Chronograph

Released in the 1970s, the Seiko Bullhead is a cult classic in the world of horology. It earned its nickname from the placement of the crown and chronograph pushers at the top of the case, resembling the horns of a bull. This design was intended to make the pushers easier to operate while driving or racing. It is powered by the caliber 6138, one of the first automatic chronograph movements to feature both a column wheel and a vertical clutch system.