I'm gonna try to answer your question, although I'm like BNB, don't have all contours of barrels for reference.....there are 3 contours, I think....the superlights are skinny, next is the regular contour which measures .650 to .675 at the muzzle, then the heavy contour of the large calibers like 44 Mag and 45-70 which measure .805 at the muzzle are thicker than the .30 cal and under regular contour barrels, but still tapered a fair amount. From my mesurements, it appears the bull barrel are the same or really close to the same measurements as the heavy barrels used with the .357, .44s and .45-70, my .204 barrel measures .800 at the muzzle.
That's the best I can do for ya..... :wink: