THE HOUSE TODAY will be voting on a provision in the Carter administration's civil service reform bill that would make it easier for Vietnam veterans to get - or hold - government jobs. It's a modest measure whose purpose is to concentrate veterans preference among those who served in the Vietnam era. Born of compromise, it is far from perfect. But on balance, it is a decided plus for Vietnam vets - a significant element in the uphill effort to redress some of the wrongs that have been done to those who served in Vietnam, or in the time of the Vietnam War.

It ought to be passed. But it has run into strong opposition from the old guard of the veterans movement precisely because it is the old-guard constituency in the established veterans organizations that would lose the most. Strict limits would be put on the lifetime preferences awarded to able-bodied veterans - preferences still used over and over again by veterans of wars long past to move from one government job to another, as well as in and out of government. A limit would also be put on the preferences available to retired veterans - those who made the armed services their career. The result would be to reduce the "pool" of non-disable veterans eligible for job preference from 27 million to 7 million - all of them from the Vietnam era - by 1980. As was noted in a recent article by Timothy B. Clark in the National Journal, "the elimination of repeated use of the preference would prevent older veterans from clogging the tops of the federal job registers."

These are sensible job-preference reforms, long overdue, not just for the sake of Vietnam-era veterans, but in the context of the larger purpose of making more rational and equitable use of preference entitlements of all sorts in an age of proliferating preferences. If it ever made sense to reward non-disabled veterans with a lifetime right to a 5-point advantage in the scores on federal job examinations, it makes a lot less sense now when the government is trying, at the same time, to give preferential treatment to a host of non-veterans - women, for example, and minorities.

But a big effort will be made, nevertheless, to knock the administration's veterans-preference provision out of the civil service reform bill, and to defeat, as well, an amendment by Rep. David E. Bonior (D-Mich.) that would give veterans who actually served in the Vietnam theater of operations more time to use their preferences. Leading the charge is Rep. James M. Hanley (D-N.Y.), with a thoroughly Orwellian argument that the administration bill is actualy bad for Vietnam-era veterans. True, it would take a little away from them with one hand, in the course of putting restrictions of one sort or another on preferences for all non-disabled veterans of all wars. But the congressman, and some of his colleagues who are circulating the same sort of disinformation in the interest of preserving the status quo for veterans of earlier wars, knows well enough that, on balance, these reforms would give Vietnam veterans quite a lot with other hand by making it easier for them to compete against older veterans for federal jobs.That's the important point - and that's why these changes in the veterans-preference procedures should be made.