Easiest thing in your situation is to turn it with the tailstock center in the muzzle. You can make a brass spud to protect the crown (make ahead of time) or Brownell's sells "crown savers" for just that purpose. you can make a hasty taper for the chamber end (rod stuck in the chuck and taper cut in place) - especially if the receiver is still attached. The steady rest would be my second choice (I'm in the same boat as you in terms of lathe size). I've threaded dozens of barrels for silencers.
Extending the barrel, or using fixed spacers defeat the purpose of having an outboard spider, which is to be able to dial in both ends of the barrel. (The spacer could perhaps prevent barrel whip, but most of us don't thread at a speed where that is a legitimate problem.)
GsT
Extending the barrel, or using fixed spacers defeat the purpose of having an outboard spider, which is to be able to dial in both ends of the barrel. (The spacer could perhaps prevent barrel whip, but most of us don't thread at a speed where that is a legitimate problem.)
GsT
