Hunters in rural Texas have quietly enjoyed and exercised the right to openly carry rifles for decades. But in recent months, as gun advocates have pushed for the passage of open-carry legislation that would allow those with concealed-carry permits to wear their handguns unconcealed on their hips, pro-gun Texans have sought to put the freedom to carry long guns to the test in Austin and other cities.

“A right that goes unexercised is a right that will be in jeopardy in the future,” said Jerry Patterson, the state land commissioner and a former state senator who wrote the concealed handgun law. “It used to be that everyone drove around Texas with a shotgun or rifle in a pickup visible for all to see. It’s normal. It’s routine. It’s lawful. We want to demonstrate that there’s no reason to call up the National Guard. Somebody might be offended, but that’s just too bad.”

Mr. Patterson, 66, who is scheduled to speak at the rally, used to carry a pistol in his boot on the floor of the Senate chamber when he was a legislator in Austin. But he will not have a rifle at the event on Saturday, because doing so, he said, would be too cumbersome.

When asked if he was bringing a rifle to the Alamo, the Rev. Terry Holcomb, a rally organizer and a pastor at a Baptist church near Huntsville, Tex., replied, “No sir, but my wife is.”