Are guns useful for defending against tyrants?

Why not ask A. Solzhenitsyn, author and victim of the Russian
Gulags:

“And how we burned in the camps later, thinking: What would things
have been like if every Security operative, when he went out at night
to make an arrest, had been uncertain whether he would return alive
and had to say good-bye to his family? Or if, during periods of mass
arrests, as for example in Leningrad, when they arrested a quarter of
the entire city, people had not simply sat there in their lairs, paling in
terror at every bang of the downstairs door and at every step on the
staircase, but had understood they had nothing left to lose and had
boldly set up in the downstairs hall an ambush of half a dozen people
with axes, hammers, pokers, or whatever else was at hand? [...] The
Organs would very quickly have suffered a shortage of officers and
transport and, notwithstanding all of Stalin’s thirst, the cursed machine
would have ground to a halt!”

The Gulag Archipelago, A. Solzhenitsyn. Chapter 1 “Arrest”, fn. 5.