It’s not uncommon to chop and thread a full length rifle barrel. If, for instance, you had a .308win with a 22” barrel but the barrel profile was not quite right at the end for a 5/8” thread, but it was correct at 18ish”, it wouldn’t be uncommon for your smith to cut it at 18”, re-crown and thread the barrel there. This would not only stiffen the barrel a bit(handy with a suppressor) but also make wielding the length of the can a bit less awkward.
