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On earlier Charles Lancaster so-called "wristbreaker" sidelocks, they used single limb mainsprings that also functioned as levers for cocking the tumblers as barrels drop. These mainsprings, combined with cams, allowed for the self-opening feature. Later, Lancaster used double limb V mainsprings that spring cocked the tumblers, while still allowing for the self-opening feature, still called "wristbreakers" too. Now, for my question: On these V mainspring versions, below the action screw for removing the lockplates, each side of action, is another smaller screw, marked "M. SPRING CRAMP" These screws were turned a quarter turn to crimp the mainsprings, freeing the tumblers, prior to removing the lockplates, thus leaving the mainsprings in the bar of the action. CAN ANYONE TELL ME THE SHAPE OF THE CAMS INSIDE THE ACTION, THAT CRAMPED THE MAINSPRINGS, AND/OR TELL ME THE DIAMETER OF THESE CAMS, OR TELL ME HOW I CAN FIND A DRAWING OF THESE ACTIONS, INCLUDING THE CAMS, OR TELL ME HOW I CAN ACQUIRE SUCH INFORMATION, FOR STUDY?