I have got 2 barrel blanks ordered from Lothar Walther,4 to 6 week wait on them , getting the reamer from Ptg , I'm going with 400 Jeffery (450/400 ) iv been letting a young man hunt on my farm for a few years , he owns a cnc machine shop so he's going to help with some of the work, decided to build a monoblock so I can let the chamber area stay on plane instead of a taper the shotgun block has , , he helped me build a couple Mauser action rifles few years ago , 9.3x62 and a .275 Rigby ,