A lock for apreciation

[fernando]

A lock for a shoulder gun, probably a regional work.
I would date it XVIII century. The plate is fixed with three screws ... a sign of age, right?
I think the cock can be called the column type.
Here and there, traces of a very simple and unpretentious decoration may be seen.
If i see it right, the name over here would be Fecho de nó (Knot lock).
The frizzen hole is so much wider than its fixing screw ... whether it is much worn, or a replacement (though it looks the original matching one ) or used to be filled with some kind of bearing ( which sounds funny to little knowledge).
In the brilliant work written in the XVIII century, Espingarda Perfeita (The perfect Gun), the authors write that the knot locks aren't accurate for firing in the air, since they are too stiff when pulling the trigger ... many persons used them because they are cheaper.
I would love to hear coments about this device, gentlemen.
Fernando.

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