A group of D.C. postal workers voiced nearly unanimous disgust yesterday with the contract negotiated between their union leaders and the Postal Service - but nevertheless predicted that Washington would be one of the last cities to join a threatened nationwide postal strike.

"This is not an industrial town," said a 15-year veteran distribution clerk who would not give his name. "These people here don't know how to handle a strike."

The same employe, interviewed outside the Main Post Office at North Capital Street and Massachusetts Avenue, complained bitterly about the terms of a tentative pact announced a month ago and since rejected by membership votes of all three major postal unions. The pact included a 19.5 percent wage increase over three years, which came close to falling within the President's anti-inflation wage guidelines.

"Nobody likes to pick up the paper and read that the postal contract is the only trophy the Carter administration has on its shelf," the employe said. "It means we're the only ones that got screwed."

Most of these interviewed on their half-hour lunch breaks yesterday had harsh words for the postal unions as well as for Postmaster General William F. Bolger, who has refused to enter new negotiations.

"We don't know anything," said one worker. "They (union officials) don't tell us anything. Basically people feel there's a lot of double talk going on."

"To me it seems like the union sold us out," said William Coates, a maintenance man who earns $14,400 annually. "You don't get the biggest raise until the third year. You really need it before then."

Maintenance and custodial workers get virtually no overtime, Coates said.

Those who have been getting the most overtime, particularly employes at the Washington Bulk Mail Center in Largo, are upset because the proposed pact would continue to authorize mandatory 12-hour days and seven-day weeks during December and other designated emergency periods. In nonemergency periods, the pact would set a maximum 10-hour day and six-day work week.

"There are some funny rules that they have," said Robert Brown, a "Power-Ox" motor operator who earns $15,300 a year. "During Christmastime I worked 10 hours on my day off and I got charged two hours of leave because I didn't work 12 hours - on my off day."

A majority of those interviewed said they woudl favor a strike if Bolder refuses to resume negotiations, but there was widespread skepticism that a strike will occur here. If the unions decide not to call a nationwide strike, there may be wildcat job actions elsewhere but probably not in Washington, the workers agreed.

"I don't think the people down here are going to strike, no way," said William McDougald, a seven-year veteran postal maintenance man who supports his wife and three children on $13,370 a year.

Like other postal workers, said McDouglad, he received a letter from te Postal Service in July reminding him that a strike would be illegal and might jeopardize his job.

"A lot of guys, they're a little afraid to come out (on strike)," said mailhandler J. T. Jones.

"I don't think these people here are as militant as they are in New York or Chicago," said clerk Clarence Wheeler, who earns $16,500 after 19 years on the job.

"I do all right," said Wheeler. "I have a wife that works. Fortunately, my wife makes more than I do."

A maintenance carpenter said the 19.5 percent wage increase was unfair, but added, "Wages is unfair, period. I don't know how some man can be earning $50,000 or $60,000 a year and say that another man don't need more than $15,000.

Another employe attributed the greater militancy of New York postal workers to a state law that enables them to collect unemployment benefits while on strike.

"That's why they don't mind walking," he said. "It's not that we're not militant. We can get militant."