The Sagebrush Rebellion boiled up with the quickness of a summer storm, seeming to gather force as it moved east. A band of ranchers and politicians from the ranges and mountains of the West, pushing for state control of millions of acres of federal lands, soon added to their legions the names of Ronald Reagan and James G. Watt.

Today Reagan is the president of the United States and Watt, as Interior secretary, presides over most of the 300 million federally owned acres that the rebels of this romantic-sounding cause once dreamed of controlling.

But like a passing summer storm, the rebellion apparently has blown over.

"I think the heat and the fever is out of the issue, that's what I think," said Joe Lane, an Arizona rancher who helped lead the rebellion there.

Here in Nevada, where the rebellion's sparks were ignited, and in other western states, the movement seems to have lost its direction. The momentum of two years ago has dissipated, the rebellion's principal goal--transferring federally controlled land to the states--appears more remote than ever, and the rebels themselves cannot agree on the next step.

"We reached a roadblock," said Dean Rhodes, a Nevada rancher and state legislator whom many consider the father of the rebellion. "We had two choices: We could call for a cease-fire, or we could take a look at other bold ideas on land management which will give state and local authorities more control over the land."

The bold new ideas include "privatization." The concept might be better left in the rhetorical dustbin of the rebellion, but the catchy name offers the possibility of raising money, and in a period of large budget deficits and a trillion-dollar national debt it may be salable politically to the rest of the country.

The westerners who consider themselves part of this movement are deeply divided over how this concept can be put in practice and indeed whether it is even sound.

Aside from the proposal of putting lands into private ownership, the theoreticians of the rebellion have found little else that is both attractive and practical. And some now say that portions of the original rebellion were a mistake.

With three bumper stickers pasted over his office door proclaiming his allegiance to the Sagebrush Rebellion, there is little doubt where Jac Shaw's sympathies lie. But Shaw, the administrator of division of state lands in Nevada, sounds like anything but a rebel these days.

"I've made some changes in my thinking," he said. One is on the question of who should control the rights to the minerals locked beneath the federal lands in the West.

"I think the mineral industry should remain under federal ownership," Shaw said. His reason, which is likely to reinforce the fear of the rebellion's opponents that rebel-controlled land would quickly fall into the hands of developers, is that mining companies would have more trouble complying with a dozen or so state laws than one federal law regulating their operations.

Shaw also has made a dramatic turnabout on another central point of the rebellion, the idea that the states would be better land managers than is Washington.

"We found in the West that state land managers are often more frustrating to the users than the federal agencies," he said.

Whatever momentum the Sagebrush Rebellion once had--and there is considerable disagreement about that----has been blunted by a variety of factors, the most important being the rebels' failure to make any headway in Congress on legislation to transfer federal land to the states.

"We probably thought we had it made with all that firepower back there in Washington," Rhodes said.

Some supporters of the rebellion now recognize that their idea lacked widespread political support from the beginning; others are disappointed that their friends in the Reagan administration have failed to carry through on their promises.

There have been smaller setbacks. An attempted legal challenge to the federal government's land policies was sloughed off by a federal district judge in Reno. The state has appealed to the 9th U.S. Circuit Court of Appeals, asking it to order the district judge at least to hear the state's arguments, but the lower court decision has demoralized some members of the movement.

Another sign of dwindling political support came recently when Reno Republicans, in a reversal, refused to endorse a Sagebrush Rebellion plank.

To some extent, the rebellion is a victim of its partial success. By dramatizing the fact that federal government has vast holdings in the West--87 percent of Nevada, for example--the rebellion helped produce changes in the way the Bureau of Land Management manages that land.

"I've got to begrudgingly say that, the issue having been raised, there is probably a new sensitivity by the agencies that manage the land," said Colordao Gov. Richard Lamm, an outspoken opponent of the Sagebrush Rebellion.

Watt's "Good Neighbor" policy--with less red tape and more consultation, at least with state officials--has eased some of the westerners' anxieties.

"Without really changing policy, Watt has made it clear he wants to listen and wants us to listen," said Larry Woodard, associate BLM director in New Mexico. "That's the kind of subtlety that changes attitudes."

Last year, Watt encouraged governors to tell him what federal lands they would like--for industrial development, parks, hospitals, city buildings and the like--and state officials report that Interior has been responsive about opening negotiations on transferring many of the parcels.

Watt said last fall his policies were so effective that they had ended the Sagebrush Rebellion. Westerners say this overstates both what has happened and Watt's responsibility for it.

Even before Watt and the Reagan administration arrived in Washington, the BLM, to many rebels the symbol of oppressive federal regulation, had begun to change.

"We used to develop our plans pretty much on our own and then present them to people and let them react," said Bill Calkins, a BLM official in Las Vegas. "Now they have an input in the development of the plans."

One of the leaders in this change was Ed Spang, BLM director in Nevada. He took over there during the heat of the rebellion and immediately set about to defuse it.

After extensive consultation with state and county officials, and with users of the land, he established a system of broad-based committees that now help make the decisions on how vast parcels of federal land are managed.

"It's not an advisory board to us," said the BLM's Bob Stewart in Nevada. "The users are leading the effort."

But many westerners are far from satisfied, and they are looking for a new way to achieve their goals. Recently, "privatization" has become the new watchword.

The word "privatization" entered the lexicon of the Sagebrush rebels last year. Steve Hanke, a senior economist on the staff of the president's Council of Economic Advisers, proposed it in a speech in Reno.

In its purest form, it means that the federal lands should be sold to private interests. The theory is that private landholders, who have an economic stake in the land, will manage it more productively and efficiently than any level of government.

Some rebels conclude that even state management of their lands would mean unnecessary bureaucracy and red tape. Some Washington officials see it as a way to reduce the budget deficit.

But others in and out of the movement are afraid of the idea. Rhodes is promoting it, but even he says he would support it only with safeguards. He is toying with a formulation that would let ranchers acquire the surface rights to land they have been using, with federal ownership of the mineral rights intact. The states would take over day-to-day management of the land.

Other westerners, fearing that their land would end up in the hands of wealthy foreign investors rather than the ranchers who now use it, are resisting the new scheme. "Some of us feel Dean has been sold a bill of goods in Washington," said one Nevadan in the movement.

Jac Shaw, who acknowledges an interest in the idea, nonetheless has mighty reservations. "An economist can be as narrow-minded as a rancher, a miner or an environmentalist," he said. "All they see is money.... It would be absolutely foolish to dump everything at the highest bid price you could get. This could destroy America. The Arabs could end up owning everything."

Shaw favors a series of experimental programs on small parcels to test various concepts of land management.

Still, opponents of the Sagebrush Rebellion recognize that the movement's new direction may be harder to attack. Gov. Lamm has been an outspoken opponent of the rebellion, vetoing a Sagebrush resolution approved by the state legislature. He says "privatization" is "less audacious" than transferring federal land to the states, but adds, "It is an equally bad idea."

But he fears it could take hold because of economic factors. "The Sagebrush Rebellion sounded good out on the hustings and out in the West, but 'privatization' is going to be harder to deal with."

The Reagan administration has taken tentative steps in this direction, but has hardly embraced the concept, in part because there is no agreement on what it is.

But rebellion leaders justify their interest in the concept on the basis of past experience.

"We've learned the original idea was politically unappealing and probably politically unachievable," said Shaw. "If we hold our head in the sand and say that's all we'll look at, we'd be in the same position we've accused the environmentalists of being in. We want to be ready to see that whatever change comes is one we can all live with and work with."