Some will shoot themselves in the foot, from cleaning accidents.
Some will shoot each other, because. "I didn't think the gun was loaded."
The rest will hose out most of their ammo in their first fire-fight, because if Hollywood has taught them anything, it's that 'spray and pray' works great for the good guys.
Then they'll all be promptly mowed down by a squadron of AH-64, supported by a couple of A-10's, then mopped up by a battalion of actual soldiers with current training, real fire-discipline, lead by officers with recent combat experience.
And that's assuming they don't get drone-struck off the map first.
This reoccurring fantasy of "We gots ur gunz to fight 'gainst gubbmint tie-rinny" is utter nonsense and has been since WW2.
You really don't know anything about how the actual military works. Where were all the Apaches, A-10s, and drones when the Bundys had their little revolt?
You forget, most of the military (and the overwhelming majority of combat arms occupations) are made up of red blooded, God fearing, white men who are (mostly) from the south.
If the US military is ever "ordered" to attack US Citizens (ones that resemble the rank-and-file of the infantry at that), that will not go over how you think it will.