The Pentagon's research director said yesterday he will begin a new offensive to try to persuade Congress that 100 rather than 50 MX missiles should be placed in existing Minuteman silos.

Conceding he had been advised that any effort to resurrect the MX was "a political no-no," Donald A. Hicks, a former Northrop Corp. executive who has been undersecretary of defense for research and engineering for the last nine months, said it would be "idiotic" to believe Congress will not listen to reason.

In another statement likely to raise some eyebrows in Congress, Hicks said during a breakfast meeting with reporters that the United States has become "a dictatorial state" when it comes to developing weapons because of "the huge number of oversight people" in government and industry.

The atmosphere has become "stifling," he said, because layer after layer has been built up as "people defend themselves against people who defend themselves" at each step of the procurement process.

He said how well current plans for reforms work out will depend in part on whether Congress is willing to back off from its attempts to manage military procurement in great detail.

In elaborating on his plan to "make another run on the next 50 MXs," Hicks said he felt it was his duty to lay out the choices. The argument that "if you bring out the facts, you screw up the consensus" supporting President Reagan's strategic program "is baloney," he said.

The nation, he said, could put another 50 MXs with 10 warheads each in Minuteman silos for $2 billion. That compares with a cost of $50 billion for 500 warheads on mobile Midgetman missiles, he said.

A force of 100 MX missiles would be "a tremendous deterrent" and could help persuade the Soviets to reduce their force of SS18 long-range missiles through an arms control agreement, Hicks said.

His support for more MXs does not mean he is opposed to the Midgetman, he said. The Midgetman comes up for a formal Pentagon review in December.

A presidential advisory commission headed by retired Lt. Gen. Brent Scowcroft recommended deploying 100 MXs in Minuteman silos while pursuing the smaller, mobile Midgetman, but Congress last year decided to limit the MX deployment to 50. The administration, however, has since proposed forgoing the Midgetman under an arms control offer directed at the Soviets.