I guess that might work in some areas, but I question how many would keep at it once bullets start flying.
Antifa shenanigans are very regional, sometimes down to the neighborhood. That's why, as you mentioned, when they head to other places they get turned away with guns very quickly. They will stay in their little victim disarmament zones, and prey on the people foolish enough to come to them. If it goes sideways (and that's still an "if" for now, I think) you'll se the little "Autonomous" or "Occupied" zones they got going on widen to encompass chunks of cities that will become EU style No-Go zones for cops and people with any sense. Inside those, they will be pretty deep into Lord of the Flies mob mentality and violence.
We've already seen it in Seattle's CHAZ, and Occupy Wall Street. Beatings and rapes were common inside those leftie controlled areas. I'd be shocked if the same thing doesn't happen at Columbia University this week. Let those Antifa run zones simmer a little longer and you'll get full on struggle sessions and beatings, and then they'll start killing people.
Bullets won't start flying (AT them anyway) because they'll keep the worst of it in areas they control. And if you and a bunch of buddies go into a University or Blue city center with enough force to clear them out, YOU'LL be the bad guys in the narrative.
So, in short, they'll do what commies always do: Keep their violence in times and places that they have overwhelming force superiority, and leverage existing structures against their foes. As they gain more power they will ramp up both violence and reach. Eventually, they will attempt to take over the armed governmental functions, and if successful, they will leverage the government against their foes. There will never be a fight where Antifa stands and fights against their opponents. They would lose that.
Or at least that's their plan.