i have ordered boring bars and other tooling to compliment my cumins and harbor freight micro mill. the place I ordered from screwed up the order, then ups screwed it up some more and damaged a box returning it to shipper. will be dec 26 to get package #1 and #3, ...#2 came monday. it all should have been in 1 box. I will be constructing a ball turner, a lever lock for the tail stock and boring bar holders. this is all to aid the construction of a big bore air gun from scratch will buy barrel, screws and springs. don't know about any one else but I am getting serious about my lathe and mill. the first gun project will be the valve, then to test it I will use some dom tubeing to test. I am pretty sure I will be using a muzzle loader barrel.....length, twist rate, and caliber from .32 maybe a bit larger and it will be co2 maybe later go to 1500 psi/ John