Least clean-up the goal? Pay a little extra for plated bullets from Berry's or Rainier. In 357 Magnum I developed a load with Berry's 148 grain plated hollow base wadcutter with 3.8 grains of Alliant American Select with a lead-free primer (PMC or CCI) that I can only describe as incredibly clean, the cleanest load i've ever shot in any gun, any caliber, my Clean+Green load. Marvelously accurate also. In 38 Spl, you would want to reduce that to maybe 3.3 or 3.4 grains of American Select & with either round, the easy-loading plated wadcutter would be seated flush with a light roll crimp around the top edge of it. No lead-free primers? Use a regular primer & the only clean-up you'll have will be derived from the primer and a slight copper wash in the barrel that will come out with the ammonia-based copper removers. With the lead-free primer, however, you can shoot about 100 of these & the revolver will look like you shot about 5 rounds.