Wearing a white, plastic hard hat and the dirt of earlier stumping at a construction site, Maryland Attorney General Francis (Bill) Burch marched into his campaign headquarters here and began lecturing about the "real lesson," of California's Proposition 13 for government employees and their unions.

Politicians, said Burch, who is running for governor, "can no longer cave into state employes unions. The message from California will move East like wildfire. The revolt is on its way. The public won't stand for it anymore. They are saying, 'Enough is enough. We will not put up with the ever increasing tax burden'."

Thus Burch, who nevertheless says he opposes Proposition 13, moved within the space of a week to add public employes to the list of targets of his increasingly fervent gubernatorial campaign.

initiative, which limits property taxes to 1 percent of the 1975-76 assessed value, to scold government workers fit in neatly with the campaign plan of carving out a constituency among conservative blue-collar voters.

Last Saturday he denounced Maryland school teachers for concentrating more on their pocketbooks than their teaching chores. Last Wednesday he accused Acting Gov. Blair Lee III of forming a ticket that "pits the rich monied interests against the middle and working classes."

He has become the most angry man of Maryland's crowded gubernatorial contest, striking out at special interests who normally attract special consideration from candidates for statewide office like public employes and teachers. By this, he has defied political convention in a manner leading some campaign observers to scratch their heads in disbelief.

"Is this guy meshugge (crazy) or some kind of human kamikaze?" asked a bemused aide to State Senate President Steny H. Hoyer a day after Burch barged into Hoyer's press conference and denounced Hoyer's plans to join Lee's ticket as lieutenant governor. "It was sheer bush league stuff."

Burch, 59, said he has "just begun to take off the gloves and fight. I'm going to speak what's on my mind. I don't care who I offend. I think the people want straight talk and that's what I'm giving 'em.

"Inside. I'm the softest person in the world, I'm one of the most sensitive people in the world," Burch said in an interview. "But when I put it into action, I get very intense and very hard. I am much tougher when I'm fighting for someone else. I'm fighting for all the people who are fed up with government today."

Burch said his campaign fervor often stays with him in his private moments, when he is off stage. Three nights ago, for instance, he got into bed and began thinking about what he would tell a group of longshoremen who had invited him to address them the following night at their Baltimore union hall.

"All of a sudden, my feelings began welling up in me," the three-term attorney general recalled. "I got terribly angry with the bureaucracy and the people in government who are keeping things from happening. I was sort of irritated and boiling. It's part of my nature that I'm really intolerant of medicority.

"Quite frankly, I'm angry at the politicians right now," he continued. "I'm burned up because they're playing political games. They're hoodwinking the public. I'm talking about Blair Lee playing the game with the political deals and playing the game with the teachers' pension. (Lee changed his stand on his pension reform proposal.)"

Burch's most defiant public act came last weekend when he relinquished any hope of winning support of Maryland's powerful teachers' union by accusing the educators at a convention of "going back to the well" for higher salaries and better pension rights while allowing school standards to fall drastically.

"It's time to take a knife to educational bureaucracy," warned Burch in his controversial speech. "The more money you get, it seems the worse the prognoisis for our children is. It is clear that over the long haul, the standard of education in Maryland has deteriorated."

The hard-hitting slogans and dire predictions of Burch are part of a gradually evolving campaign style that began a year ago in a more traditional vein. Until a few months ago, he spent most of his energy raising campaign funds and issuing conventional political pronouncements.

Within recent weeks Burch's campaign changed direction. He negotiated a controversial plea-bargaining deal with the convicted Pallottine mail-order specialist, which he later admitted hurt his candidacy. His campaign was lagging badly in the polls. Money was difficult to raise.

Burch and his staff retreated to Florida three weeks ago to rethink strategy and reevaluate the advice of professional campaign consultants. "The consultants were doing everything traditional," and Philip Altfeld, Burch's campaign manager.

"Finally I came out of the closet and said it's my campaign," Altfeld recalled in a interview. "I said, I'm going to take my lumps or get my kudos. Dammit, we're coming out.'"

Last Saturday night, Altfeld said, he joined Burch and his wife Pat for a "working dinner" at an ornate eating club on the campus of Towson State University. "I took a yellow pad," said Altfeld, "and I said, Bill, we've been talking around things for a long time. Now let's talk to them.

"I mentioned I wanted his feeling about unions, about the bay bridge, about criminal justice, and he started giving me his point of view. His eyes were flashing, he starts pounding the table and yelling. Pat is saying, 'Billy, keep your voice down.' He told her he didn't care who hears him.

"What Bill Burch has seen and feels is that all the candidates have one thing in mind - get elected at all costs," said Altfeld. "The thing about Burch is, nobody and nothing is sacred to him. He's going to express that to the public."

Burch's new strategy hopes to project him as a populist candidate with a conservative streak. He has tried to develop that picture in recent days by performing several "working man's jobs," including tending bar at a Baltimore County night spot and swinging a hammer at a Baltimore construction site yesterday.

Driving up to the construction site in his silver, chauffeur-driven Mercury, Burch posed for pictures as he pulled out nails from boards, knocked down a wall with an 8-pound sledge-hammer and tore apart a window frame with a crowbar. He told laborers there that he did the same work when he was a high school student.

The image of the working-class hero conflicts with Burch's noncampaigning life style. He is a millionaire businessman who lives in an affluent Baltimore neighborhood and owns vacation homes in Florida and Ocean City.

But the life style differences do not create a conflict for candidate Burch, he said. "I started with absolutely nothing," he told a reporter. I lived the life of everyone of these men. I've done every kind of work imaginable. On the docks, at the steel plant and on the trucks. I can show them there isn't a job that I haven't done.

"From the age of 14, I've been working on the average of 14, 15 hours a day. I did it the hard way and I'm proud of it. I don't think anyone will resent me for it."

While Burch was using the Proposition 13 vote in California to talk about his candidacy yesterday, other candidates in Maryland's gubernatorial race were also giving their reaction to the controversial measure.

Acting Gov. Blair Lee III said "As a symbolic matter it's wonderful, like a breath of fresh air. But as a practical matter it leaves California with breath-taking problems . . . It's going to send shock waves across our country . . ."

However, "The property tax burden in California is much higher ($415 per capita) than it is in Maryland ($239 per capita)," Lee said.

"The legislature and my administration . . . mounted a pretty effective war on the property tax," (in the last session), he said.

Theodore G. Venetoulis, another Democratic hopeful, said, "I think the underlying issue is management of government. When voters believe that there is waste and inefficiency in the operation of government, they strike where the democratic system allows them to strike: in the vote booths . . .

"The kind of voter outburst in California yesterday is consistent with the expressions of frustration and anger over high taxes and government waste and mismanagement that I'm hearing from Marylanders."

Candidate Harry R. Hughes campaign manager, Joseph Coale, said "People have had enough with the inefficient and irresponsible government. There's a limit to what people will tolerate . . . it means people want a more equitable tax structure. Hughes was responsible for instituting the graduated income tax in Maryland, and if we didn't have that the property taxes would be worse, if you can believe that."

Walter Orlinsky, president of the Baltimore City Council, said, "We are about to start a period of reevaluating the relationship of state and local government, and who pays. If Proposition 13 weren't around in its current form, those issues would still be talked about. I am edging toward a combination of limits on government spending and a limit on property tax increases myself."