Barrel Ribs and Observations

[ArtS]

In the other thread I just started, I loaded some pictures of the Parker Laminated barrels I just recieved today from Breck. He had posted a picture of them in his long running thread on Rib Art. He commented on the appearance of the bottom rib on my barrels. After reading the entire thread and was struck by the seeming inconsistency of ribs on barrels. I am posting four photos and would like to see if anyone has any comments on the history as to the variations.

The guns in the first two pictures are, right to left, an 1880 grade 3 lifter 10 gauge with 30" Parker Laminate barrels, a 1901 DH 16 gauge 28" Damascus, and a 1905 GH 12 gauge 25" Damascus. All barrels are refinished.

The 10 gauge barrels are Parker Laminate, but the top rib appears tp be a convential laminate of a similar scale. The 16 gauge barrels are finer textured Damascus to match the grade but the rib is matted. Whether it is plain steel or Damascus I don't know. The 12 gauge barrels appear to be a more basic grade of Damascus but the top rib looks to be made from a higher grade of damascus than the barrels, just based on pattern dimensions. My impression may not be correct but the top rib looks distinctively different the barrels on this third gun.

The bottom ribs are really surprising. The 12 gauge bottom rib is Damascus and of a similar size and quality to the barrels. The 16 gauge bottom rib is Damascus but of a pattern and size completely out of proportion to the delicate barrel pattern. The 10 gauge bottom rib is surprisingly Damascus and one of the finest and tiniest patterns I have seen. Zoom in on the third picture to see a closeup. The icing on this cake is that the fourth picture shows the lowere rib behid the barrel lug and it appears to be yet another material which appearsto be twist to my eye. It certainly doesn't appear to be the same material as the top or bottom rib.

I find it amazing that one set of barrels would be constructed of four different materials.

Does anyone know if this was common; that ribs were randomly selected during construction? I have an earlier Lifter that I haven't examined yet, and if I remember correctly it is Damascus with a smooth solid steel top rib.

I know that you could get about anything you wanted but I have never seen type of rib listed in any order that I have viewed and I know there couldn't possibly been that much word of mouth information exchange. Anyone know if there was ever a standard on rib specs?