Was a police officer’s off duty gun. He bought two guns back in 1968 (saw the receipt) I skipped out on the Colt Python but grabbed this a single. It is becoming my EDC. It‚‚s doable anyone might have a custom made barrel size for your King Cobra, but it https://www.primmaryarmshop.com/product-tag/colt-king-cobra/?per_page=6