Montgomery County Executive Charles W. Gilchrist, disputing some school officials' arguments for hiring hundreds of teachers next year, recommended yesterday a $472.6 million school operating budget that falls $4.9 million short of the school board's request.

Gilchrist's recommended funding, however, would be an increase of $35 million, or 8.1 percent, over this year's budget.

In a memo released yesterday, Gilchrist said his recommendation is 1 percent less than the school board is seeking and is one of the smallest cuts since fiscal year 1972.

The school board has requested an operating budget of $477.5 million, of which about $27 million would go toward hiring 415 teachers to cope with an expected influx of elementary school students. That money also would be used to reduce class sizes at all grade levels and to add more kindergarten classes.

Gilchrist's largest cut was a $2.2 million reduction in the funds for new teachers. Under Gilchrist's proposal only about 300 new teachers would be hired.

He said in the memo that he is recommending hiring fewer teachers because there is no room for adding classes in elementary schools to reduce class size until new schools are built in the northern areas of the county, where rapid growth has caused a boom in enrollments.

He also said the school system could save money by doing a better job of balancing small and large classes at high schools. He added that the county expects 300 fewer secondary school students in 1987 than does the school system.

School Board President James Cronin said Gilchrist's recommendations "lack logic."

"There seems to be a mindlessness to the cuts," he said. "It seems they had a preconceived number that they were going to cut from the budget and they found the same old tired areas to cut from."

School board members, as well as Superintendent Wilmer S. Cody and other school officials, went before the County Council last night to pitch their proposal. The council has until May 15 to adopt a budget, and need not accept Gilchrist's recommendations.

Gilchrist's recommendations include:

* Eliminating the school board's request for 26 teachers to reduce high school class sizes, and eliminating 23 of the 46 it wants to hire to reduce elementary class sizes.

* Giving the school board about $819,000 less than it has requested for administration. The school board proposed hiring 45 additional administrators. Gilchrist would trim that to 36 positions.

* Cutting $428,980 in the board's request for instructional materials and supplies.

* Providing about $791,000 less for student transportation. Part of the reduction is to take into account lower fuel prices.