The post-Vietnam experiment of trying to fill the ranks of the peace-time military entirely with volunteers is working so well that there is no need for the draft, in sight, according to the Pentagon's manpower chief.

Dr. John P. White, in taking that position during an interview with The Washington Post, dismissed the recent political talk about returning to the draft as "more smoke than fire."

Even with the upcoming sharp drop in the nation's population of 18 year olds. White said, the Army, Navy, Air Force and Marine Corps should be able to keep filling their ranks with volunteers.

A shortage of 18-year-old males, he said, could be offset by taking more females into the services.

Other responses planned, he said, include reducing the dropout rate within the services and inspiring more people in the service to reenlist.

Although several lawmakers have recently been warning that the "all-volunteer force" is not working and some kind of compulsory national service may have to be legislated, White countered that such suggestions fly in the face of hard numbers.

In contrast to the mid-1950s when the armed services took 75 recent of the eligible took 75 percent of the eligible 18-year-old males. White said, today they need only about 20 percent of them. Reasons for this include a smaller infantry - 2 million on active duty in 1978 compared to 2.3 million in 1954; longer enlistments; a larger teen-age population to draw from, and more women in the ranks.

The services should not have to recruit a significantly higher percentage of the 18-year-old males between now and 1985, White said. He predicted the total recruited would still be close to the current 20 perent of those eligible. (The United States had 1.8 million militarily eligible 18-year-old males in 1977 and is expected to have 1.6 million in 1985.)

White and his Pentagon colleagues have declared war on the dropout rates of the services to reduce the need for new volunteers. The Army, for example, saw 42 of every 100 men who signed up in 1974 drop out before finishing their obligated tours. New goals to reduce attrition have been set for all the services.

"There are several things" driving demands to returne to the draft, White said, despite what he considers the proven success of the volunteer system.

"One, which is a legitimate social issue, is the question of whether or not people have an obligation to serve in some way.

"If you really look at that, it comes back down to some kind of national service" for young Americans that would require creation of additional government service agencies to absorb the young people the military could not use.

Or, to put it another way. "back to the CCC," the Civilian Conservation Corps established by President Frank-hn D. Roosevelt to combat unemployment during the Depression.

Critics of the all-volunteer force, White said, tend "to hold it up for comparison against some poorly defined but clearly better system. The impression is that there is always an alternative that will work better.

"If you give us more people" by going back to the draft. White continued, "you're going to shorten the tour length. If you shorten the tour length, I'm not going to be able to train them as well."

White acknowledges there are problems in the all-volunteer force. "You bet your life we have (them)," he said. "Anybody who recruits between 350,000 and 400,000 people a year is going to have problems." Congress could help the Pentagon with these problems by approving legislation for managing the force better, such as more flexibility in giving bonuses to service people, White said.

Chairman John C. Stennis (D Miss.) of the Senate Armed Services Committee has referred to reported short-comings of the all-volunteer force, in urging that alternatives be considered. Sen. Sam Nunn DGa.) has similarly called for a fresh look at alternatives.

A yearning for "the good old days" is another part of the political impetus for going back to the draft, White believes.

White, who was a lieutenant in the Marine Corps from 1959 to 1961, said "I am bemused by surveys and TV shows from Europe which quote captains of the infantry as saying the Army isn't like it was during the draft. The captain talking wasn't in the Army when we had a draft. He's never seen anything but a volunteer soldier." (Draft calls ended in December 1972.)

Also, said White, some people want to return to the draft to obtain a bigger U.S. military force. "As I go around" talking about the all-volunteer force, said White, I hear that "it isn't big enough."

However, given the statistical and political realities, "the press is over-playing 'here comes the draft'" stories, White said.

"When you translate those legitimate concerns" about the current all-volunteer force "into registration and conscription," the political sentiment for shifting back melts away, he said.

The toughest test ahead for the all-volunteer force will come between 1985 and 1990 when the 18-year-old population dips.

Asked if he expects the draft to be reinstituted during his scheduled four-year tour of duty at the Pentagon, barring war, White replied without hesitation:

"No, I do not, I do not see either any need nor any sentiment for it. There's more smoke than fire."