(Were original Parkers brazed?) Only at their breech, & while not certain I don't think 21's were either. As they had mechanical connections at the breech I seem to think they had no Brazing at all. To get away from the heat required for brazing was after all the only advantage to the mechanical joining (& advertizing of course).
6-Bear; To get down to the Nitty-Gritty of the matter bbl regulation has little to to with "Point of Aim, the stocking looks to that. BBl regulation is strictly for the purpose of making both bbls shoot to the same point. "Both" O/U & SxS can (And Often Do) disperse their charge away in either a horizontal or vertical direction. This is of course most apt to occur in lower priced guns which are not regulated & one can rest assured any gun having "Brazed" ribs was not regulated.
