The Washington Bullets began to test the limits of their aspirations and imagination with the onset of training camp yesterday at Fort Meade as 21 would-be players met for a pair of two-hour-plus workouts that officially started the 1985-86 season.

"Well, I've got one under my belt, but then again I usually don't start to count them this early," said newly acquired forward Dan Roundfield after the first session. Yet with only a week before the Bullets' first NBA exhibition game, an Oct. 4 date with Patrick Ewing and the New York Knicks, there really isn't much of an opportunity to ease into the swing of things.

"The way I see it, we've only got two weeks to get ready," said Coach Gene Shue. "There's this week, then the first game and then another four or five days until the next one. After that, we're going to constantly be in and out."

As a result, there was perhaps more full-court scrimmaging than one would expect on opening day, usually more ceremonial than anything else. Mundane drills were replaced by live action as Shue and his new assistant, Fred Carter, began force-feeding the system to the players.

Three of them -- center Tom McMillen, forward Darren Daye and guard Frank Johnson -- sat out because of assorted injuries. Jeff Ruland, however, was a willing and active participant. Sporting a wispy tail of hair on the back of his head and a three-inch scar on his right shoulder, the all-star center said he was feeling no ill effects of this summer's surgery.

"I'm here and I'm ready to go," he said. "Why should I take it easy? I've had two months of rehabilitation and a month of lifting weights. I'm ready."

He did look strong, as did Roundfield and forward Cliff Robinson. However, the players who drew the most response from a surprising crowd of more than 100 spectators were Kenny Green and Manute Bol, the Bullets' first- and second-round choices in last June's draft.

Green drew some oohs and aahs when he caught a bad pass in stride and recovered sufficiently enough to take off from outside the lane for a soaring dunk. The mere presence of 7-foot-7 Bol is enough to force an intake of breath, but there was a good amount of applause, too, especially when he dunked the ball from the wing on a fast break, then got back on defense in time to spike a jump shot out of bounds.

That was a fairly common occurence yesterday. Playing one-on-one with Bol, Robinson started a drive to the basket, only to suspect in mid-air that the shot would be blocked. Robinson then floated beneath the basket for a reverse layup, only to find that Bol still was there. A smile on his face, Robinson finally came down to earth, unable to get off a shot.

It has been generally thought that it will take Bol a couple of years to get to the point where he could contribute regularly to the team. General Manager Bob Ferry, though, has revised that timetable.

"I would suspect it will be quicker than that," he said. "The only thing that would limit him from getting playing time and contributing is injuries."

Even with the presently unwieldy numbers in camp, one could see the lines being drawn for some future battles that will ultimately affect the composition of the team. There should be a spirited skirmish for the Bullets' fourth guard spot between Dudley Bradley, Tom Sewell and Guy Williams, all members of last season's squad.

Williams, disappointed in the team's decision at the end of last season not to activate him for the playoff series against the Philadelphia 76ers, was a free agent, yet chose to re-sign with the team, as did McMillen.

"They brought me in early and showed good faith in me," Williams said. "They rehabilitated me (following a severe knee injury during his senior year at Washington State). I can't let them go yet."

Another player competing for a spot in the back court is Clarence (Foots) Walker, 34. An 11-year veteran, the last five with the New Jersey Nets, he was ready to call it a career when Washington approached him.

"I had called some camps earlier in the summer but I always got the runaround or they told me they were going with youth," he said. "I had an offer from Converse to be a representative, I was thinking of starting a restaurant, and after 11 years I just wanted some time for me. The Bullets called me on Wednesday though and made an offer that I couldn't refuse, so here I am."

The possible need for another point guard arose because Johnson is still recovering from surgery on his right foot. Although present at the practices, he was reduced to shooting leisurely at side baskets away from the main floor.

"Everything's going well but it should be another two weeks or so before I can go out there," he said. He is to be X-rayed and reexamined Oct. 16.