I have pushed pellets through a .22 smooth twist, they had a very subtle flower petal shape to them with I think 5 petals? but you had to look close to see it, to the naked eye they just looked smooth.
The barrels are turned down on the O/D for the last 3" of the their length before the swaging process, then a sleeve is fitted over the swaged smaller dia section and the barrel O/D ground and blued. You need to look very carefully to see the join!
HFT, for people with only 2 buttucks!
VooDoo TwoTwo The next chapter.