Federal officials who ignore or punish whistle-blowers may be in for a painful jolt from the fledgling outfit set up by the Carter administration to investigate dirt that agencies too often sweep under the bureaucratic rug.

Although only a month old, the small (25 employes) Office of the Special Counsel already is causing some rumblings in government, from federal triangle to the midwest.

Groups that have been critical of the government's war on corruption -- including congressional offices and representatives of special "public service" groups -- are anticipating good things from the office. So far, they like its vigor and approach.

"We know it is there," one government-watcher said, "and we know it has investigators out and whistle-blowers calling in. We are just waiting for the first couple of cases, and hoping for a blockbuster or two."

OSC officials are playing it close to the vest. Insiders say they have 180 to 190 cases under investigation, and that it has a potential "hit parade" of investigations nearing a climax that could make national headlines.

Officials of the agency, a spinoff from the now defunct Civil Service Commission, refuse to discuss specific cases. Nor will they say what agencies, employes or officials are being probed for alleged misconduct, political abuses or improper personnel actions. Independent investigation by this column indicates the OSC has been looking at some serious agency warts.

The OSC was created under the new Civil Service Reform Act to deal with personnel allegations of the type that plagued the Nixon administration -- HUD, GSA, HEW and other agencies -- and contributed to "little Watergates" in the bureaucracy. Working alongside the Merit Systems Protection Board -- also a CSC spinoff -- the Office will have power to bloc agency reprisals against employes who point out wrong-doing. It can take its cases directly to department or agency heads or in the case of department and agency heads themselves, directly to the President. Congress also will get regular reports on specifics of what the OSC is doing, and why.

Some government-watchers hope for a couple of "big, solid" cases early on, to show that it has the will and clout to do things, and to convince federal and political brass the office is not a fly-by-night outfit. The fact that General Service's Administrator Jay Solomon is having the rug pulled from under him has depressed corruption fighters in government. They are hoping the OSC, while not in the same jursidiction, will have better luck and better support.

"We don't want to try cases in the newspapers," an official said when asked last week about details of some on-going investigations, but he did confirm they are taking place. His superior, Patrick Swygert, the special counsel, said most actions would be in the public domain when investigations are completed.

Similar past investigations by the Civil Service Commission seldom drew much blood, because they generally were kept secret. As an independent agency that must get funds annually from Congress, the special counsel's office must justify its existence with results.

Some cynics believe the office will be sandbagged by the Washington power structure, a bipartisan network of career officials and politicians whose primary goal is to keep the boat from being rocked, and avoid embarrassment. In that respect they may have a genuine hard-ball player in Swygert, who runs the office.

He had been general counsel of the CSC and knows the political and bureaucratic ropes.

Swygert also is considered one of the sharpest lawyers, and a master diplomat, in a government town full of sharp lawyers and master diplomats. Swygert also is one of the highest ranking blacks within government and of the Carter administration. He's from the career (legal) ranks, and has had a number of job offers from government, and industry. So fear of losing a job because of excessive-toe treading is not a major threat to him.