Bem-vindo Gustavo
The barrels have a very interesting pattern, which is a variant of Laminette Simple

[Linked Image from photos.smugmug.com]

BUT the Twist segments are, I believe, Bernard Twist which I've never seen

[Linked Image from photos.smugmug.com]

[Linked Image from photos.smugmug.com]

The barrels were double proved to 16,356 psi by crushers which would be about 18,000 psi by modern transducer measurement. The barrels should of course be evaluated for defects and adequate wall thickness before using the gun.

BTW the ends of both firing pins are pointed and need to be reworked

[Linked Image from photos.smugmug.com]

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