Hand chosen for the ultimate in accuracy. Button rifled, stress relieved, hand lapped, air gauged and optically inspected to ensure that each one falls within the Select Match category. That means within .0003" of specs and uniform over the entire bore to within .0001". Not threaded or chambered. 416 stainless. #7 contour only 28" (71.2cm) long. (See Shilen chart Shilen.com for dimensions). Mfg: Shilen