Dutch's methods work, and his materials that tell you how to go about working up an accurate load for your gun work, too. Dutch did learn all this through much trial and error, and years of working on the issues, one at a time. You can also e-mail him directly if you have a question, or call him at the phone number given on his materials. At $15.00, I consider it a very good investment, and encourage all the readers here to acquire the information. He also provides a practice target to use, that you can take to a Xerox company and make as many copies as you like.