It's a 5 pin Grade 6 Stan. Wow.
Another one of Walt's; a 6 pin with "American Flag" and I believe a Gr. 5
This is Wayne Owen's Gr. 6 6 pin with 4 Iron "Turkish"
The barrels look to be 3 Iron Crolle, but if you'll post a full size close up of about 8" of barrel where the contrast is most apparent I'll "read' the pattern.