[Hugh]

All the "new" German field armory replacement bbls I have used would hand tighten to within a extractor slot or close. New after market bbls vary, some will come close, some won't, most will require a little turning on the face of the flange to fit. As Rick says, be sure to use lots of antisize compound on the threads and flange. I have had bbls that would require tightening and loosening several times to mate the bbl to the receiver in the correct position.