Dynalectron Corp. announced yesterday the successful completion of the largest refining of shale oil into synthetic fuel.

A Dynalectron subsidiary, Hydrocarbn Research Inc., produced 11.300 gallons of the aviation fuel which met or exceeded all military specifications. The project was done under a U.S. Air Force contract with a subsidiary of Sun Oil Co.

The project is another in a series of synfuel projects undertaken by the McLean-based technological company.

The announcement was made as Dynalectron stockholders met in McLean for the company's annual meeting.

Dynalectron reported profits of more than $4 million last year, rebounding from a rocky 1978 when it showed a loss of more than $1.5 million.

Armed with 1980 first-quarter results in which the company showed a profit of about $1 million -- five times the 1979 first-quarter profit -- C. G. Gulledge, Dynalectron's president and chief executive, said the firm expected continued 1980 growth.

In particular, Gulledge cited the expected passage this year of the Carter administration's synfuels legislation and the increases in the nation's defense budget as evidence of solid prospects for Dynalectron.

Dynalectron has made a substantial investment in synthetic fuels programs, so the $20 billion in the synfuels bill along with price guarantees for synfuels producers would aid the company's growth, the company president said.

"We are pleased that the legislation is in sight despite continued proscrastination by a few members of Congress," Gulledge told stockholders.

Recent statements by Defense Department officials indicating that the government intends to overhaul its equipment before developing new defense systems also bode well for Dynalectron, Gulledge said.

Such an overhauling effort could have a "substantial effect" on Dynalectron, he said, pointing out that the company has a number of major maintenance contracts with the federal government.