Nothing special about that action. Very typical. Many times the lever would be on the left side of the action on the English made guns. The long strip on the bottom of the action is the spring for the underlever. These actions usually lock using just one bite on the rear lump. W&C Scott made oodles of these. I restored a Wm. Moore & Co. gun using a very similar action a few years ago. Very simple. Robust. Well made.

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