I've found that by using different dipping methods I can vary charges by nearly a full grain with some powders. Use the "Lee method", push the dipper backwards and strike the mouth w/straight edge or dip, shake, dip again, or push dipper through powder mouth first or push dipper through mouth first twice. All will give different charges. I double check my method with a scale with every powder I dip. But consistency is the key, what ever method you choose, do it the same force, same speed, same way every time...