The longest revolver barrel I have carried on duty is 1 7/8 (S&W 642 BUG). But my Dad is a retired LEO and while he only carried 4" guns, I know a few of his comrades carried 6" revolvers. The duty gear of today is nowhere near as impressive as a low slung revolver and rows of shiny bullets. Always made me think of my Dad like a Marshall in the old West. My stuff us all dull kydex and polymer.