I would like to thank Marshall for helping to set the record straight on this cartridge. The Rifle that Mike and I put together was built on the Ruger M77 Roundtop. When Ken Waters came out with his article, he had used the very same action. I was the one who sent the letter to Mr. Waters. I was wanting to know what he thought of using the 300 barnes X bullet with H322 powder. I still have his reply around here somewhere. This is a very good short action large caliber cartridge. I was getting 2350 FPS from the Barnes 300 grain X bullet out of a 21.75" barrel and 54 grains of H322. This rifle was eventually rechambered to my 2nd of 2 416 Taylors that I have owned.