In a large saucepan, heat cream and milk to 175°; stir in 1/2 cup sugar and salt until dissolved. Whisk a small amount of the hot mixture into the egg. Return all to the pan, whisking constantly. Cook and stir over low heat until mixture is slightly thickened.
Remove from the heat. Cool quickly by placing pan in a bowl of ice water; stir for 2 minutes. Stir in sour cream and jelly. Press waxed paper onto surface of custard. Refrigerate for several hours or overnight.
Meanwhile, in a small bowl, gently combine raspberries with lemon juice and remaining sugar. Let stand for 2 hours, stirring occasionally. Mash raspberry mixture slightly; stir into custard.
Fill cylinder of ice cream freezer two-thirds full; freeze according to the manufacturerâs directions. Refrigerate remaining mixture until ready to freeze. When ice cream is frozen, transfer to a freezer container; freeze for 2-4 hours before serving. Yield: 1-1/2 quarts.