These weekend warriors form the obdurate bedrock of Trump Nation: white, rural and working class. They vote, and they are heavily armed, right down to the .22-caliber derringer fired by Nadine Wheeler, 63, a retiree who calls her tiny gun “the best in feminine protection.”

During two days of conversations, grievances poured forth from the group as effortlessly as bullets from a gun barrel. On armed excursions through sun-dappled forests, they spoke of a vague but looming tyranny — an amalgam of sinister forces to be held at bay only with a firearm and the willingness to use it.

They are machinists and retirees, roofers and factory line workers, all steeped in the culture of the rural South. They say Mr. Trump, a Manhattan billionaire and real estate tycoon, speaks for them.

“Within the extreme right, many of Trump’s most passionate backers come from the militia movement,” said Mark Pitcavage, a senior research fellow at the Center on Extremism at the Anti-Defamation League. “The militia movement is overwhelmingly behind Trump’s candidacy.”

For militias, Mr. Trump’s anti-establishment views “play right into their paranoid style of politics,” said Ryan Lenz, editor of the Hatewatch blog at the Southern Poverty Law Center.

The Georgia Security Force is noteworthy among militias for its acute Islamophobia, Mr. Pitcavage said. Its members are so-called 3 percenters, who believe that only 3 percent of colonists fought in the Revolutionary War. That is “a historical myth,” said Mr. Pitcavage, a historian, but useful for those who believe a few people with guns can defeat tyranny.