Justin, the sprials are the Twist. All Damascus barrels when they are rust blued and then boiled, will come out black. In order to see the Damascus pattern, they have to be dipped in an etching solution from 5-10 seconds, and then immediately flushed with running water to stop the etching.
English guns of old were browned, no boiling, but also etched.

Last edited by JDW; 09/23/12 03:44 PM.
David