A Republican senator is releasing evidence to back up his contention that the Reagan Justice Department stifled allegations three years ago that defense contractors and private consultants were illegally obtaining Pentagon weapons secrets.

Sen. Charles Grassley says the massive Pentagon bribery investigation now under way could have started much earlier during the Reagan administration.The Iowa Republican said he planned Monday to read into the Congressional Record testimony that was blocked by the Justice Department in 1985 from being delivered to a subcommittee he chaired.

The October 1985 testimony alleged that private consultants were regularly receiving classified details about U.S. weapons systems, Grassley said in an interview Sunday with The Associated Press.

"The Justice Department could have pursued this aggressively more than three years ago but they didn't," he said.

The 2-year-old probe has focused chiefly on Navy weapons-buying. It became public last week when FBI and Naval Investigative Service agents conducted coast-to-coast raids on the offices of past and present Pentagon officials, private consultants and contractors.

U.S. Attorney Henry Hudson has said privately that perhaps as many as 200 indictments could be expected out of the investigation, a government source said Sunday.

In October 1985 Grassley was chairman of the Senate Judiciary administrative practices subcommittee, a panel which he used to examine defense procurement practices. Grassley is a frequent critic of what he calls widespread waste and abuse in Pentagon spending.

Grassley said Justice Department officials blocked the testimony of Robert Segal, a Defense Department investigator who was the Pentagon's liaison with the Justice Department's Defense Procurement Fraud Unit. The DPFU was a special Justice Department office set up to investigate waste in the military budget.

Grassley said the allegations predated the current investigation. "This goes back much before what we're seeing now," he said.