Some of the staunchest friends of government workers and retirees are hoping that congressional budget-balancers will take back a retiree cost-of-living raise that went into effect on Sunday. It would serve as a warning to the public, they contend, about the cuts some in Congress would like to make in all government benefits.

The pensions of more than 2 million former federal employes and military personnel are being increased by 3.1 percent, a raise that will show up in January checks. There are about 100,000 retirees in the Washington area.

The raise, also going to Social Security recipients, reflects the increase in living costs during the last year.

Although there are a number of high-price pensioners in the federal retirement community -- including two former presidents and hundreds of ex-members of Congress -- the typical civil service retiree gets about $960 a month, according to the National Association of Retired Federal Employees. The typical survivor of a federal retiree gets $460 a month.

Senate-House conferees are considering a budget-balancing plan, the Gramm-Rudman-Hollings debt ceiling amendment, that would cut into cost-of-living adjustment programs such as the retiree raises. The latest 3.1 percent raise alone is going to cost $1.6 billion a year.

Consideration also has been given to cutting increases in benefits for black lung victims and putting a cap on Social Security raises. But the latter is such a hot potato -- it would affect one in every six Americans -- that it has been removed, for now, from serious debate.

Although it is considered unlikely that Congress will take back the adjustments that have already gone in effect for federal-military retirees, some federal union officials say they would secretly like it to happen.

"Right now our people are out there alone," a union lobbyist said. "The conferees are trying to get a foot in the door to cut all cost-of-living adjustments in the future by getting at federal retirees first. Obviously we don't want that to happen. . . . "

But if it does, he said, it will "show the public . . . what is in store for people under Social Security and other programs."

He said that "every day that passes without action increases the chances that Congress won't take back the retiree raises.

"But what if they do? How is it going to look if they have to stop payment on the January checks for retirees, or cut their February checks to recoup the raise that they got and then lost?

" . . . It would be a disaster for some of the retirees, but it could be a public relations dream for those of us who have been warning all along that the Gramm-Rudman plan is a horror show for everybody in the country."