In its first major discussion of "Sting"-type police tactics, the U.S. Court of Appeals here affirmed yesterday the convictions of two Washington men who sold a sawed-off shotgun to undercover police officers who were posing as underworld fences for stolen goods.

The court rejected arguments by the two men that they had been prejudiced by intense pretrial publicity, the playing of portions of their own video-taped conversations not directly relating to the crime with which they were charged, and by the judge's refusal to instruct the jury on the defense of "entrapment."

"Finding that none of these contentions warrants reversal, we affirm," said U.S. Circuit Judge Roger Robb for himself and Circuit Judge Edward A. Tamm in a 2-to-1 written opinion.

U.S. Circuit Judge Spottswood Robinson III said he would have reversed the convictions and ordered new trials for each of the two defendants for different reasons.

He said the conviction of John J. Hazel Jr. should be reversed because the judge refused to instruct the jury on the defense of entrapment that Hazel raised during his trial. Hazel had contended that the undercover officers at PFF, Icn., an operation that became known as the "Sting," kept urging him to bring them guns to buy and would pay him for bringing in customers.

Robb said, however, for the majority that the fact that Hazel came to the warehouse operation 18 times "negates even a colorable contention that Hazel was an innocent person instigated to crime by the police . . ."

Robinson said the conviction of Anthony J. Brooks should have been overturned because of the videotape of the transaction in which Brooks and Hazel sold the gun to the police included Brooks' brag that his "main hustle" was stealing. Robinson said playing that portion of the tape was unfair to Brooks and might have prejudiced the jury against him.

Robb wrote for the majority that he felt prosecutors were unnecessarily "painting the lily" by including Brooks' general statement on stealing in their otherwise strong case against him. But he said he did not believe that was reason enough to reverse Brooks' conviction.