JOYS POPCORN BALLS

1 package brown sugar
1 C white corn syrup
1 stick butter
1 can sweetened condensed milk
3 gallons popped corn

Combine sugar and corn syrup in a medium saucepan, stirring constantly, until mixture comes to a boil. Add butter and continue cooking until it boils again. Add milk and bring to a boil again. Cook over medium heat, stirring constantly, until it forms a soft ball in cold water. Pour over corn and mix carefully.