Winchester model 12 barrel removal

[Welderboy250]

I need to do some work on a 12 gauge model 12 barrel. I have the barrel bare other than the lug at the chamber end. I took out the screw for the toothed block and slid it back before threading the nut off the end of the barrel. Haven't gotten the lug to move. My question is if the thing is pressed on or threaded. Hopefully someone can tell me. Thanks