Butter one side of four slices of bread, and place the slices buttered-side down on a large piece of wax paper on a flat surface. Top each with a slice of Swiss cheese, and then divide half of the corned beef among them.
Using paper towels, squeeze out excess moisture from the sauerkraut. Divide the sauerkraut among the sandwiches, and top each with one tablespoon of Russian dressing. Add another layer of corned beef and a second slice of Swiss cheese to each sandwich. Top with the remaining bread slices; butter the side facing out.
Preheat a griddle or frying pan to medium heat. Cook the sandwiches on one side until the bread is golden brown. Use a spatula to carefully flip the sandwiches over and finish cooking on the second side. Cut the sandwiches in half before serving.