THAT WAS SOME way for the railway unions to begin their contract negotiations with the railroads. Within 24 hours of the first meeting, labor chief Al H. Chesser denounced management as regressive, unenlightened and stupid, while calling for Congress to consider nationalizing the railroads. An "in-depth" study of nationalization is necessary now, he said, because the nation "can no longer stand the folly of rail-management irresponsibility to the country."

It is advisable, of course, to take with a grain of salt anything said publicity by anyone negotiating a labor contract. Outrageous rhetoric is often thought by one party or another to be a useful way of concentrating the minds of those on the other side of the bargaining table - or those in government who might wish to lend a hand. What is different about this rhetorical flourish, however, is that it is not just a loud shout; it represents, in fact, an abrupt change in Mr. Chesser's position on the question of nationalization: He always used to oppose to it.

Two parts of the nation's railroad system have already been nationalized: Conrail, which has finished its first year running the once-bankrupt roads in the Northeast and Amtrak, which operates almost all of the nation's passenger trains. Both, it is interesting to note, are costing the taxpayers a pretty penny. Amtrak is on a permanent federal subsidy because it is clear that 1) most long-haul passenger trains are a money-losing proposition and 2) Congress is not prepared to have them go out of business. Conrail is dipping heavily into the federal treasury for rehabilitation and replacement funds, although its managers insist that some day it will be able to show a profit. When each of these nationalized systems was established, railway labor came out of the political negotiations in Congress rather well. We have to think those two things - federal money and political negotiations - were in the back of Mr. Chesser's mind when he called for Congress to complete a study of total nationalization in six months, just about the time when the unions will be free to strike under their existing contracts.

The real ssues in these negotiations, however, will not be nationalization - almost no one thinks that is a good idea. They will be money, work rules and that old railroad tradition of getting a day's pay for either eight hours of work or 100 miles of travel. It is encouraging that the unions, despite Mr. Chesser's outburst, have indicated a willingness to talk about that distance-time rule. In an age when trains can cover 100 miles in one hour or less, a 100-mile working day is an anachronism that should long since have been discarded. It would be a big step forward for the railroads if, under the cover of talk about nationalization, it could finally be done away with this time around.