That's true. I was making the point (contra OP) that your owning a gun has little to no impact on the government ability to oppress you. Widespread gun ownership is not some magic pixie dust that will keep the federal government from oppressing us, and strict gun regulation is not some kind emasculation that will prevent the citizenry from rising up against a tyrannical government (c.f. Egypt, Libya).
This would only work if the revs were in response to a truly tyrannical act, say if a president were to declare a state of emergency and indefinitely suspend elections. Think of the Arab Spring, Waco Texas, or the negative response to police brutality on the OWS protestors. Think of the imagery (and it would of course be filmed) of a hardy group of patriots facing off against tanks and bombers. These are powerful political images and could bring in diplomatic pressure, outside military aid, etc.
I'm not saying a revolt is likely likely to succeed, I'm just saying it more complicated than a cut and dry, "they have bigger guns, so the revolutionaries lose."