I just picked up a unfired 300 Large shank Rum barrel. I had the smith turn down to small shank, cut and crown to 19". $45.

As Devine indicated, the barrels bore was used to indicate. When the shank was turned there was a .020 rise in material on one side and the rest of the new thread was even with the new shank of the barrel. It was done correctly!

Barrel is a real shooter!

Neal