Administration tacticians assigned to get President Reagan's controversial federal pension reforms through Congress this year are split into two camps.

One group, which takes the Office of Management and Budget position, favors a take-the-money-and-run approach. Although this group isn't advertising it, it would settle for half a loaf this time around. That would be to get Congress to raise federal workers' contributions to the civil service retirement fund from 7 percent of salary to 11 percent. That would bring in more money, as would the proposal to hold down cost-of-living raises for retirees under age 62.

The other faction favors the tougher line of the Office of Personnel Management. OPM wants to push for all the proposed retirement reforms, even though the House has already rejected them and the Senate, despite its Republican margin, seems to have little stomach for the reforms, which have enraged the federal work force.

In addition to rejecting the retirement reforms, the House has also voted to give federal workers a 4 percent raise this October despite the president's plea to cancel the boost. The Senate has taken a middle ground. Its budget committee would okay a 4 percent increase, but defer it until April 1984. The point is that the administration is--so far--batting zero in Congress with its federal personnel changes.

OPM's political team--just bolstered by a top-level reshuffle of nearly 40 career and political appointees--is philosophically committed to getting all the proposed pension changes. This team feels that raising the contribution rate for employes must be accompanied by new legislation that requires feds to work longer--and pay into the fund at a higher rate--to get full benefits.

Congressional aides who are watching the pension reform battle feel that the only way the reforms will win is if the Senate attaches them to a bill, or a budget, that the House could not turn down. Finding one of those won't be easy. But as an OPM aide said Monday afternoon, "The opera ain't over until the fat lady sings!" That means the OPM hasn't abandoned the fight for a full plate of proposed reforms despite the rejection slips from Congress.