Winchester 1886 Extra Heavy barrel dimensions|Winchester Rifles|Forum|Winchester Collector

 Travis, I don’t know what TTT means but I can say that Arthur Pirkle in his book on page 69 lists the dimensions of 86 barrels. Diameter at breech 1 3/16″ plus or minus 3/32: muzzle 1″ plus or minus 3/32.

 It is my opinion that heavy and extra heavy on a letter simply means that was how it was recorded in the ledger, not one was bigger than the other. That said some barrels are much bigger, sticking out past the receiver, these may letter by the pound like a Sharps or just be called extra heavy.

 One theory is the heavy barrels were bored then machined octagon parallel to the bore, thus making the variance in size. T/R

 Travis, A heavy or ex heavy is big enough that the barrel bottom has a radiius machined in the bottom, forearm cap is special, and the forearm wood is thin on the sides. These features are easy to see when viewing  pictures of the gun. The idea that a heavy barrel is just a little bigger than a standard and a extra heavy is a lot bigger is not my opinion. T/R