Preheat the oven to 190°C.
Mix the flour with the baking powder and salt. Add the butter and rub together with your fingers until the mixture resembles breadcrumbs.
Add the orange zest and the milk, then the raisins. Mix well with a spatula until you get a soft dough.
Put the dough onto a lightly floured surface and knead, then roll out to about 2 cm thick.
Using a 7-cm cutter (or a glass) stamp out rounds.
Put the rounds on a lined or greased baking sheet. Brush each scones with a little milk.
Bake for 15-20 minutes until risen and light brown.
Transfer the scones to a wire rack to cool.