Bill, the original gun was a Quality/Grade O 16 hammer gun with original 26" Twist barrels. Last January, Edgar called me and said a friend had picked up the 28" set of Twist barrels, but didnt need them. I bought them, and they almost snapped on, probably would have, but didnt want to force them. Dave Fjeline fit them up for me. I seem to shoot the longer barrels much better.