You can give this chart a try.

http://www.ebrew.com/primarynews/mis...ing_charts.htm


Sweetening Wine

2 ounces of sugar will raise 1 gallon of wine by .005 in specific
gravity;
therefore,
2 ounces will raise 5 gallons by .001

Dry Wine .990 - 1.000
Medium Sweet 1.000 - 1.008
Sweet Wine over 1.008