Efforts to break the deadlock among Senate natural gas conferees failed again yesterday, but Sen. Henry M. Jackson (D-Wash.) said he is still optimistic and will try again today.

In an effort to get the Senate conferees off dead center, Jackson, Chairman of the Senate Energy Committee, had proposed lifting price controls from newly discovered gas after seven years.

Yesterday 8 of the 17 conferees, including six of the seven Republicians, offered a counter proposal which Jackson and five other middle-of-the road Democrats working with him flatly rejected.

The Republican plan would deregulate new gas in five years and would permit prices to rise at a much faster rate during the interim.

No Jackson's staff estimated the Republican plan would cost consumers $33 to $38 billion more than the House bill by 1985, compared to $9.2 billion under Jackson's offer.

Jackson has given up trying to reach an agreement among Senate conferees before the start of a 10-day Senate recess Friday. But he has backed away from his statement that if the conferees don't agree this week they might as well give up.

He hopes a meeting with some of the conferees today will "define the problem areas" and permit staff to draft a compromise during the recess.

Jackson said he felt "we were within reach of an agreement" last Friday after he had held several meetings with Sens. Bennett Johnston (D-La.) and Pee Domenici (R-N. Mex.), among others. Both had supported deregulation, while Jackson supports President Carter's plan to continue price controls at higher levels.

Jackson also hoped to win over Sens. Wendel Ford (D-Ky.) and Mark Hatfield (R-Ore.) to support his offer. But on Monday all the Republican conferees met with Ford and Johnston and agreed to stick together, at least for one more attempt. Yesterday, it failed.

Jackson said he will meet this morning with Johnston and Domenici and try again to put together a majority for a gas compromise which they could then offer to House conferees.

The conference on Carter's energy bill, which was his top legislative project last year, has been bogged down waiting for the deadlocked Senate conferees to make an offer and start the negotiating process in the conference. The House voted to continue controls, while the Senate voted deregulation after two years.

Jackson went to the White HOuse yesterday to tell Carter that he still believes it is possible to reach a natural gas compromise that Carter and his supporters in congress can support.