THE IDEA that gun control is involved in the debate over the Alaskan lands is absurd. Yet the National Rifle Association, and some members of Congress, are peddling that line as part of an effort to beat the Udall-Anderson bill. It is as ridiculous as the other myth now being created about Alaska: that somehow the nation's energy problem will be alleviated if all the land in that state with oil potential is opened to exploration, but not if only 95 percent of it is.

The gun control idea grows from the fact that the Udall-Anderson bill, supported by the Carter administration and most conservation groups, would close about 30 million acres to hunting. The Dingell-Breaux bill, backed by the NRA and the state of Alaska, would close about 20 million acres. The difference, according to Sen. Ted Stevens (R-Alaska), makes the Udall-Anderson bill "a serious gun-control threat to Americans."

The NRA, alerted to the issue by one of its directors, Rep. John D.Dingell (D-Mich.), is lobbying hard for his bill. (It is,presumably, a one-third less land.) The injection of this phony issue into what was once a serious debate over Alaska's future shows how frivolous much of the oppsition is to the Udall-Anderson bill. The problems facing Congress in trying to sort out the differences between that bill and the two competing proposals are difficult enough without this kind of diversion. But it is not unlike he numbers game that is being played with Alaska's oil.

The number 30 billion keeps cropping up. Sometimes it is used to suggest that Alaska's oil could almost make the nation energy independent. Sometimes it is used to describe what is at stake in this year's debate. Either way, it turns the decision of Congress on the Alaskan land bill into a major energy issue.

While the number is real, it is the total estimated oil reserves of Alaska. That's enough oil to make the country energy independent for, perhaps, a decade if it could be used immediately - which it can't be. Two-thirds of that oil lies offshore, an area not involved in this year's bill. The rest lies under land, 95 percent of which will be open to exploration regardless of which bill Congress passes. The other 5 percent is the Arctic Wildlife Range.

Like the gun-control issue, the energy issue is being used to confuse what is really at stake in the House of Representatives this week. That is wheather the federal government will preserve for future generations those parts of Alaska not needed for that state's orderly development now. Of the proposals before the House, the Udall-Anderson bill comes closest to keeping that heritage intact.