Bro. Steve has an amazing video of his Bernard damascus barrel fabrication, from stacking the lopin to finished product, with relevant snippets from La Fabrication des Canons Damas
https://www.youtube.com/watch?v=AFrZulegvFs

Additional commentary regarding his 2 Iron crolle barrel here
https://docs.google.com/document/d/1jQPuv4yOXpTppdXkAiyGj6LC5bXDAYBCR1DME9lB0JM/edit