Carroll County voters went to the polls yesterday in numbers greaterthan predicted and, in early results, appeared to deny U.S. Rep. Beverly B. Byron, D-6th, an eighth term.

With 13 of the county's 35 precincts reporting, voters:

* Gave Thomas Hattery, a Frederick County delegate, a lead over incumbent Byron for the Democratic nomination for Maryland's 6th Congressional District. Hattery had 12,823 votes to 10,342 for Byron, with96 of the precinct's 216 precincts reporting.

Byron trailed across the district, even in her home county of Frederick. The congresswoman was not available for comment last night.

* Selected Roscoe Bartlett, a Frederick businessman, to be the Republican candidate to runagainst the Democratic nominee in the November general election.

* Decided to keep seven of the nine appointed members of the Charter Board. Incumbents Charles Cull and C. William Knill were trailing, with Republican challengers Lanny Harchenhorn, a former state delegate,and Richard Yates, who previously has run unsuccessfully for county commissioner and school board, leading.

* Chose Cheryl McFalls andC. Scott Stone to run in November for the vacant seat on the county Board of Education. How ever, Neil McGregor, who withdrew from the race after the deadline, had a healthy vote total.

* Voted to elect Judge Francis Arnold, who was unopposed, to the Circuit Court.

In spring-like weather, the turnout yesterday was slightly better than election officials had predicted.

Politicians said the contested race for the county Charter Board was probably responsible for the heavier-than-expected turnout.

"I think Carroll will be higher (in turnout than the rest of the state) because of the charter board," said state Sen. Larry Haines, R-Carroll, Baltimore, as he was leaving his polling place at West Middle School in Westminster yesterday evening.