[Ron Wood]

You are leaning in the right direction. It is roll-die impressed, and the roll direction was from left to right as evidenced by the upset or "piled up" material on the right periphery of the marking. Now, having said that, I would guess from the unevenness of the rays on the sunburst that the die was a commercial or gunsmith die from a house such as Flukiger (but not Flukiger) and not from the Swiss Waffenfabrik Bern. From your very excellent photo, if it was an engraved marking, the "chop marks" from engraving would probably be evident. There isn't any, so that further indicates a die stamp.