North Carolina Gov. James B. Hunt Jr. was harshly criticized yesterday for his decision not to pardon 10 persons convicted on charges stemming from a 1971 racial disturbance in Wilmington, N.C.

Supporters of the group, known as the "Wilmington 10" accused the governor of engaging in "political expediency," catering to "racist" elements in his state, and - as put by the National Urban League - settling for "halfway measures that do not correct a monstrous miscarriage of justice."

The "halfway measures referred to Hunt's announcement Monday night that be would reduce by seven to eight years the 20-to-29-year prison terms being served by nine black men convicted of firebombing and conspiring to harm police and firefighters in the 1971 incident. The reductions Rev. Benjamin F. Chavis, who led mean that eight of the men are eligible for parole this year: the ninth, the Rev. Benjamin F. Chamvis, who led the group, is eligible in 1980.

A white woman, convicted as an accessory, was paroled last year after spending two years in prison.

In the wake of President Carter's human rights drive and the adoption of the 10 as "prisoners of conscience" by Amnesty International, a London-based human rights group, the case has become an international cause celebre. As if to highlight that point, the Soviet news agency Tass joined in the chorus of criticism yesterday, saying that Hunt's decision was another example of repression by "racist" U.S. officials.

The case also attracted much attention last year when three key witnesses recanted testimony that North Carolina law enforcement officials and others believe was largely responsible for sending the 10 to jail.

Hunt had been under pressure since last spring to intervene in the case. But he delayed any action until this month after the 10 lost the last of a series of attempts to have their convictions overturned in state court.

Hunt said yesterday that this decision not to pardon the 10 is final. But some members of Congress, including members of the Congressional Black Caucus, and other "Wilmington 10" supporters vowed to take their cause to the Justice Department, to Carter and "to the court of world opinion."

Congressional Black Caucus Chairman Parren J. Mitchell (D-Md.) said he would vote against any human rights amendment that comes to the floor of the House to protest the continued imprisonment fo Wilmington 10 members.

Mitchell said it is "rank hypocrisy" for the United States to push human rights abroad white "the stain of gross violation of human rights is within our own borders . . ."

Much of the outrage expressed yesterday seemed to be the product of sheer disappointment. There had been hope that Hunt, who has cultivated an image of being a moderate, "New South" politician and who has appointed blacks the state banking and public utility commissions for the first time in North Carolina history, would pardon the 10 after reviewing their case.

Indeed, when it was learned last week that the governor would make a public statement about the case, some supporters of the Wilmington 10 began calling reporters, telling them to "get ready for a pardon."

Yesterday, supporters were wondering why Hunt even bothered to call a press conference. "As a newsman, can you tell why he would make a big deal to do something like that?" a Congressional Black Caucus staff member asked a reporter.

There was also speculation yesterday, in and out of North Carolina, that Hunt, a Democrat, had done himself political harm through his decision.But that speculation was not shared by white Democratic politicians in the state, many of whom reactedfavorably to Hunt's action.

State Sen. Melvin Daniels, a banker who represents the conservative northeastern part of the state, said Hunt's action in reducing the prison terms probably would not please many whites, but added: "In a no-win situation, that was the only thing he could do."

At least 1.65 million of North Carolina's voters are white, while blacks account for 540,000, or 15 per cent. Black political leaders in the state, who are adept at turning out their share of the vote, had been pushing for a pardon.

Commented one state government source: "He [Hunt] was right on the nose politically."