My pea brain is still trying to process all this, but am starting to see a pattern. There are lots of pics up now on the PictureTrail album
http://www.picturetrail.com/sfx/album/view/21182597Lower grade guns mostly had a Twist or Laminate rib of 2-3 non-twisted layers of alternating iron and steel. US guns were universally roll-graved with obscures the rib pattern
Higher grade guns might have the same product as the barrels, but the rib was oriented so the
surface of the barrel became the
side of the rib as shown on this Remington 'Etoile' barrel. The rib extension shows the flat laminate section
The British, who criticized the Belgians for being more concerned about appearance than strength, used the ribs as a nice embellishment for their guns, and were less likely to roll grave the ribs
The ONLY mention of rib production that I could find was from:
The Gun and Its Development: With Notes on ShootingWilliam Wellington Greener Edition 3 1885
http://books.google.com/books?id=LAsAAAAAQAAJ p. 265 "Ribs are forged from rods twisted in the same manner as described for the manufacture of Damascus iron. They are then forged to the required shape upon a grooved anvil. Plain iron ribs are used for very common guns, in which case they are rolled for the gun to the required shape."
It is clear that rib manufacture was another specialty of the gun maker's art, with a knowledge base that was part of, but in addition to, pattern welded barrel technology.
