The Virginia Senate unanimously approved a bill today that would outlaw the sale and possession of Teflon-coated, armor-piercing bullets--a measure that is significantly tougher than a bullet bill passed by the House and advocated by Gov. Charles S. Robb.

The House and Senate also split today over a controversial proposal to create an intermediate state court of appeals, which Robb has called a top priority because only those with "extraordinary patience or fat wallets" can afford to appeal a trial verdict. The House gave preliminary approval to the bill, but a similar measure fell one vote short in the Senate.

The bullet ban, sponsored by Sen. Wiley F. Mitchell (R-Alexandria), was once considered by Robb, but dropped after sparking opposition from the National Rifle Association. Instead, the Democratic governor proposed a weaker version that would make it a felony to use the deadly bullets in commission of a violent crime such as murder and rape.

Critics, including Mitchell, argued today that the Robb proposal is virtually meaningless. "It doesn't do much good once a police officer is killed to charge the man who killed him with using the wrong kind of bullet," Mitchell said. "Anybody who's mean enough to kill somebody is not likely to spend a lot of time worrying what kind of bullet to use."

The Teflon-coated bullets have aroused concerns among police organizations because they are capable of piercing the lightweight, bullet-proof vests worn by many officers. Such concerns prompted the Alexandria City Council to pass a bullet ban despite vigorous opposition from gun owners who said the measure would infringe on their constitutional rights.

When Del. Samuel Glasscock (D-Suffolk) offered an amendment in the House today to ban the bullets, it was rejected. Such a move, said Del. Richard J. Cranwell (D-Roanoke), would stifle "research and development" by munitions companies, such as the Radford Army Arsenal in Montgomery County, Va., one of the area's biggest employers.

"If they want to develp munitions, they can't do it in Virginia even if it's to sell it to the military," Cranwell said. "That seems kind of absurd to me."

Glasscock, though, blamed the voice vote defeat on the state's influential gun lobby. "These folks are just scared as hell of the NRA," he said of his colleagues.

The bullet bill, which may end up being resolved in a House-Senate conference committee, was only one element in a Robb anti-crime package that also included measures to stiffen penalties on child pornography, expand the use of evidence obtained in wiretaps, create a prosecutors' right of appeal and eliminate the controversial "exclusionary rule," which forbids the use of evidence illegally obtained by police.

Except for the exclusionary rule, which died in a House committee Saturday, all other elements of the package appeared to be heading for passage today.

The House voted 55 to 39 to approve the intermediate court of appeals, but only after amending the bill to require General Assembly approval again next year before the court would begin hearing cases in 1985. Virginia is the largest state without such a court and one of two states that do not guarantee at least one appeal for those convicted of crimes or those who lose lawsuits.

In the Senate, however, the measure was derided as "a lawyers' relief bill" by Sen. Dudley J. Emick (D-Botetourt), who led a vociferous group of mostly rural legislators opposing the measure. "How many citizens have come to you and said, 'I can no longer live without the intermediate court of appeals,' " Emick asked.

Sen. Joseph V. Gartlan Jr. (D-Fairfax) attacked Emick for his "cheap shot" against lawyers, and Mitchell called Emick a "master of hubris and hyperbole." The Senate then voted 20 to 19 for the measure, only to launch into a protracted debate about the number of votes needed to approve the bill.

The senators finally decided by a 22-to-18 vote that the bill, because it created new positions, needed the approval of a full majority, or 21 senators, and so it was defeated. Sen. Edward M. Holland (D-Arlington), who sponsored the bill, said he will try to steer the House-approved measure through the Senate later this month. But Holland added, "To lose one this close is real tough."