I would think any cast was built into the action or lock plates.. that surely was the stockers job, from behind the lock plates down through the wrist/
Many crossover and heavily cast guns were built with fully swept actions from the action flat back with swept lockplates and components therein. The top tang and trigger plate follow the center line of the stock hand.
The lock internals are mainly gracefully set over to the swept line of the lockplate and often the only 'normal' right-angle interactions are the sear/bent and their alignment with the tumbler axle, everything else swinging in 2 planes.
I think I am right in saying that usually the tumblers hit the strikers is a oblique direction.
