It sounded like the U.S. equivalent of Latin America land reform - the government promising to split up the big holdings and distribute the pieces to the little people.

And that's the way many of the nation's farmers, politicians and reporters have perceived the administration's announcement last August that it was going to enforce a 75-year-old law limiting Western farmers to 160 acres of federal irrigated land.

The Wall Street Journal recently likened Interior Secretary Cecil D. Andrus to a "six-foot-seven, 280-pound bully" trying to "seize" the farmers' land. And a group of California landowners denounced the plan as a "revolutionary social experiment."

And when it became known that Andrus was thinking of amending the original plan, proponents of reform denounced the administration "sell-out."

But the actual impact of both the original plan and the modified one, it is now becoming clear, will be far less than the outcry would suggest.

Only one per cent of the nation's formland now receives irrigation water from federal dams - and most of this land will not be affected by the regulations since the owners or operators already are in compliance with the "160-acre" law.

The 9.5 million acres that presently receive the water comprise only 27 percent of the irrigated acreage in the eest.

Both the August proposals and the Andrus modifications would allow farms far larger than 160 acres. And, in any case, the average irrigated farm in California today is only 164 acres, and in many other western states the averages is even less.

The Andrus modifications, which were circulated late last month, would allow a farm family to own up to 1.280 acres of federally watered land. They also state that "farmers should live on the farm or in nearby communities," but they make clear that the residency requirement would be phased in over a generation rather and imposed "abruptly."

Interior Department officials say the new proposal tightens some aspects of the regulations announced in August. For instance, it closes a loop-hole that would have permitted large families to accumulate more than 1.280 acres by assingning extra acreage to minor children.

Like the August regulations, the new plan requires acreage to sell it by lottery - a measure designed to prevent "insider" deals wich have kept land in large corporate holdings up to now.

One high-level Interior Department official said of the Andrus proposal: "It's being perceived as for to the right. But I'll let you in on a little secret: it's to the left of where we were."

However, officials also say that the new proposal is not substantially different in its overall impact from the regulations announced last August - a fact that has drown criticism both from other administration officials and from Capitol Hill.

Sen. James D. Abourezk (D.S.D.) claimed last month that the Andrus proposal is so weak it amounts to a "sell out" to conservative western interests.

The Andrus plan also appears to ignore most of the key conclusions drown by the Department of Agriculture in an exhaustive study of western irragated land.

On Jan. 25, Secretary of Agriculture Bob Bergland urged Andrus in writing to consider limiting the amount of land that could be leased by farmers on irragated land; asking the recipients of subsidized water to pay a bigger share of the costs; and adopting a more flexible standard for determining how much irrigated land a farmer could own or lease.

Director of Economics Howard Hjort said last week that the Andrus proposal "does not go as far as would be indicated by the studies and the secretary's interpretation of the studies."

"We're not engaged in any big argument," said Hjort. "Interior is the lead agency. But it would appear there is need for further modification of Interior's proposal."

According to David Weiman, an outspoken advocate of broad land reforms, no more than 100 to 200 "growers" would have to give up land - although he added that the number of corporations and absentee landlords might be considerably higher.

In the San Joaquin Valley's West-lands irrigation district, where owners and farm operators have launched a strong lobbying campaign against the August regulations, there are only 216 farming operations in all. Of the total 530,000 acres served by federal water in the district, nearly 100,000 acres is owned by a single corporation - the Southern Pacific Railroad. And this company already agreed to divest itself of excess irrigated acreage before the August regulations were announced.

The Department of Agriculture calculates that 2.3 million acres of western lands are ineligible for federal water because they exceed the maximum holdings under the August regulations.But of those acres, about one million do not receive water from federal projects - so there would be no need for their owners to divest them.

Officials say that the new regulations apparently would have little effect on what happens to a substantial amount of the remaining 1.3 million excess acres.

About 190,000 acres get water under special provisions of the law, and could continue to do so.

Of the land that is receiving water but would be ineligible for it if the August regulations take effect, 89 percent is in the Imperial Valley Irrigation district and in various Corps of Engineers projects in California. However, court rulings that placed these projects under the 75-year-old "160 acre" law are expected to be appealed - a process that could take months or years.

According to Agriculture's study, "if the Imperial Irrigation district and the projects served by the Corps of Engineers are excluded, less than 500,000 acres of land are likely to be sold."

In addition, 315,000 acres of irrigated land considered in excess of the ceiling was earmarked for sale before the regulations were issued. The agreement to divest the excess was a condition for getting the federal project water in the first place.

About 225,000 acres in Westlands is in this category, including huge holdings of corporations and absentee owners. According to Don Upton, assistant executive director of the Westside Farmers representing Westlands, these owners don't object to selling the land, but wish to sell to "buyers of their own choice."

Broad issues of fairness and equity in the management of the nation's agricultural economy are at issue in the present dispute over the water rules. Huge taxpayer financed dams in the Western Mountains provide farm operators with subsidized irrigation water - an important economic advantage.

By allocating water, the federal government has sometimes been in the position of deciding which group of the Nation's farmers get rich.

For instance, the Agriculture Department found that a 640-acre fedeaally irrigated farm in the Columbia River basin could have had a net income of $189,000 last year, while a dryland Nebraska wheat farm with that amount of land could have lost $79.

Department officials say their main concern is that the benefits go to family farmers rather than to large corporations or wealthy absentee investors.

In Westlands, which began receiving water from federal projects in 1968, there are more than 4,000 owners of the 216 farming projects. Many of these investors receive income from renting huge tracts of irrigated land.

In the continuing controversy, Sen. Frank Church (D-Idaho) has recently emerged as the strongest congressional backer of a 1,280 ceiling.

Church is drafting a bill hhat would write this ceiling into law. However, a Church spokesman said he is opposed to the residency requirement, and prefers instead a "proprietorship test" that would assure that the owner would farm the land for at least 10 years. "You're not going to be able to check a guy's fingernails for dirt," the spokesman said.

On the other side of the spectrum, a bill sponsored by Sens. Gaylord Nelson (D-Wise.), Floyd Haskell (D-Colo.) and Abourezk would allow a maximum of 640 federally irrigated acres owned and leased by one family - half the amount in the Church proposal. But the Nelson bill would allow owners to sell excess irrigated acre-age to whoever they want - a provision that some say could make possible "insider" deals.