A bill to raise Virginia's beer drinking age by a year to 19 died in a House Committee today, the victim of animosity against Northern Virginia and some finesse by one of the General Assembly's most influential committees.

House Majority Leader Thomas W. Moss Jr. of Norfolk, chairman of the General Laws Committee and an ardent opponent of the bill, agreed that the measure would not stop teenagers from illegally obtaining beer.

"Futhermore, the only area of the state where there was any sentiment for the bill was in Northern Virginia and we're not going to change the entire state law for one area," Moss said of the bill, sponsored by Northern Virginia Republican Warren E. Barry of Fairfax.

Barry had pushed for the bill, citing a dramatic rise in teen-age alcoholism in the Washington suburbs. His proposal was similar to one approved recently by the Maryland Senate and now pending in the House there, which would raise that state's drinking age to 19 from 18.

Barry and other supporters of the bill charged that Moss and other Tidewater lawmakers opposed it because it would prevent 18-year-old sailors stationed in Norfolk and young tourists at Virginia Beach from drinking.

"The committee's heavily laden with Tidewater members and all those teen-agers coming there to drink are a great part of the economy there," said Barry. Still other critics complained that Moss, a lawyer who has represented several bars and liquor stores in Tidewater, had a conflict of interest on the bill -- a charge Moss denied.

"I didn't hear one word from anyone in the liquor industry on this," said Moss.

Barry, who counted 10 votes on the 26-member committee for the bill, thought he had won when he learned two weeks ago that one of the bill's opponents, Del. Alan A. Diamonstein D-Newport News) was hospitalized with a back ailment. With Diamonstein absent, the bill would have passed 10-9.

After a public hearing, Moss took the unusual step of delaying action on the bill for two weeks. It finally came up for a vote today after Diamonstein had returned from the hospital.

"I'm a close friend of Tom Moss, but he played a very active part to make sure this bill was bottled up in committee," complained Barry, who agreed to have the bill carried over until 1981 -- which dooms it for this year's session. Barry said the bill would have passed on the House floor had it escaped committee.

"That doesn't make any sense," responded Moss, who said he held up the bill in order to give Barry a chance to recruit more support on the committee. "He said at the start he only had 10 votes and 10 votes wasn't enough," said Moss.