The Federal Reserve cut discount rates on loans to banks, today, by a half-percentage point, sending stocks up.

The action had an immediate positive impact on Wall Street after weeks of losses. The Dow Jones industrial average initially shot up more than 300 points right after the opening bell. By midmorning, stocks had given up over half of the inital surge with the Dow up about 60 points.

The decision means that the discount rate, the interest rate that the Fed charges to make direct loans to banks, will be lowered to 5.75 percent, down from 6.25 percent.

The Fed did not change its target for the more important federal funds rate, which has remained at 5.25 percent for more than a year. Friday’s move was not expected to have an immediate impact on consumer borrowing.

However, it has been infusing billions of dollars in money into the banking system over the past week to keep that rate from rising above the target level.

Private economists praised the action by Federal Reserve Chairman Ben Bernanke and his colleagues, saying it should help steady jittery markets although many expect a cut in the federal funds rate to follow.

The move to cut the discount rate will not have a major impact on consumer interest rates in the way that cutting the federal funds rate triggers an immediate drop in banks’ prime lending rate, the benchmark for millions of consumer and business loans.

However, Friday’s move was expected to help with a severe cash crunch facing many businesses, including mortgage companies, which are having trouble getting loans for short-term financing needs.

Economists predict the Reserve will cut the discount interest rate by another 1/2 percent, soon.