Miller, IMHO, you may be missing a point. I would expect that the rear of the locking cam would engage the back of the "lump" and unload the hinge pin and hook. Since the lever pivot is substantial if not massive, the cam to lump joint should support a very significant forward shear load. If the hinge joint is unloaded, the opening moment (rotational force) will be around the cam/lump joint and there will be bending force only between the lever pivot and the breech.
Perhaps someone can confirm/refute this hypothesis.
DDA
