I have a Roux-actioned (snap-lock, under-lever) Drilling made in 1911 in Zella-Mehlis and retailed by W. Müchler und Söhne, Neuenrade, Germany. It's 9,3x72R (D) with 2x 16/65 shot barrels. There are 3 firing pin springs held in a close cluster arrangement. Those present are of different sizes suggesting they're replacements and they're all rusted and broken. A variety of new replacements have been tried but they're all too generous in width and the adjoining coils catch on each other on discharge. The result is the energy is diffused, the primer barely marked and the cartridge is not fired.

It's the suspicion of the gunsmith working on this gun that the original springs were square in section and thus avoided this problem, having more energy and less width. Would anyone be able to either (1) confirm this and/or (2) suggest where replacements (or suitable material to fashion replacements), can be found ?

This action type was once quite common and still frequently offered for sale so this problem today cannot be unique, surely ?