Joseph Coors Sr., 85, a magnate of the storied brewing company who used his fortune to underwrite conservative causes, including Ronald Reagan's political career and the Heritage Foundation, a public policy research organization, died March 15 at his home in Rancho Mirage, Calif. He had lymphatic cancer.

Mr. Coors's grandfather, a German immigrant, founded the Golden, Colo.-based, Adolph Coors Co. in 1873. Many credit Joseph Coors's engineering innovations and often-controversial business tactics with transforming the company from a regional brewery into one of the nation's largest.

He retired as chief operating officer in 1988 and remained a director until three years ago. Much of his tenure was spent working with his brother Bill; their desks were feet apart.

Born into a family that shunned ostentation and emphasized discipline, the tall and handsome Mr. Coors became of the most talked-about men in the economic and political worlds. He was an apostle of self-reliance and free enterprise, but his brusque and distant manner made him a polarizing figure among his family and the larger world.

Shunning media attention, he often worked behind the scenes to address public policy he felt had gone amok. He founded a television network, Television News Inc., or TVN, to counter what he considered the prevailing liberal slant of the mainstream media.

A Reagan supporter since the late 1960s, he became a powerful presence in Washington overnight when Reagan became president in 1981. He successfully pushed the hiring of Coloradoans, and he lobbied for the appointment of James G. Watt as secretary of the interior.

With a $250,000 grant in the early 1970s, he helped start the Heritage Foundation, which sponsored influential papers on defense and economics that shaped many of the Reagan administration's policies.

He also was a major backer of the John Birch Society, the Free Congress Foundation and groups that funneled money to conservative congressional candidates.

Praising capitalism, Mr. Coors could also be pointedly disdainful when speaking of liberal forces he felt were responsible for social rifts in the United States. Those same forces, he felt, caused the "loss" of China and other countries to his ultimate bete noir, communism.

Mr. Coors's political activism extended to the early 1950s, when he found in Russell Kirk's seminal book, "The Conservative Mind," and the National Review magazine succinct voices addressing his concerns.

In a rare interview, he told the Wall Street Journal in 1981:

"Freedom of action -- the freedom to start or carry on a business and act in a responsible fashion, to be successful -- is basic to the capitalist system. If a person had these freedoms, as my grandfather and father had, then he is able to build up an operation, as long as it is done on the proper basis -- obeying the law and without abusing anybody along the way, not misusing your freedoms."

This outlook, he added, did not guarantee success, but "the opportunity is there."

Coors, a Golden native, was born into a family whose victories and tragedies were well-chronicled.

Adolph Coors shepherded the company through much of Prohibition (producing malted milk and near beer) and then reportedly jumped to his death from a hotel room in Virginia Beach in 1929. Joseph Coors's older brother, Adolph Coors III, was kidnapped and killed in 1960.

Dan Baum wrote in his biography of the Coors family that Joseph Coors's personality was incalculably shaped by a stern household whose patriarchs discouraged dissent.

Joseph Coors was a 1939 chemistry graduate of Cornell University, where he also received a master's degree in chemical engineering. He did early research engineering work at DuPont Co. in Delaware and the National Dairy Products Association.

He joined the Coors company in 1948 and worked in its brewing and ceramics divisions. He played a central role in refining the cold-filtered process and starting one of the country's first large-scale recycling programs for aluminum cans, offering a penny for each return.

Much of his legacy is shaped by the enormous control he was said to have exerted over every aspect of the brewing, including his insistence that new employees be given lie-detector tests.

It was said that the company's insistence on certain ingredients made the brewing process more expensive than any other domestic beer. And it was largely as an issue of quality that company leaders framed the debate when Coors's practices in controlling distribution led to the Federal Trade Commission's successful suit on the grounds of price fixing, limiting competition and other illegal practices.

A few years later, in the mid-1970s, Mr. Coors won a nearly 20-month strike that ended union representation at the brewery. Even though Coors employees turned down Teamsters representation, the AFL-CIO led a decade-long boycott of the company.

His prominent role in the strike made him a target of a variety of interest groups, which accused the company of violations of labor and environmental laws and bias against gays and other minorities.

Those claims were "absolutely untrue," Mr. Coors told The Washington Post.

He continued to push the company as a national entity capable of competing with Anheuser-Busch and Miller Brewing.

He also became increasingly active in Washington politics and became a member of Reagan's Kitchen Cabinet of advisers.

His marriage to Holly Coors ended in divorce.

Besides his brother Bill, survivors include his second wife, Anne Coors; five sons from his first marriage; a sister; 27 grandchildren; and eight great-grandchildren.