I form my 256 Newton cases from WW270 cases. I first anneal them in my Giraud annealer and resize in full length RCBS dies. I lost two due to shoulder dents out of 100 using Pacific Hornady Unique case lube. As printed the Speer number one manual load data I posted above in this thread a year ago is way overboard. The best load I use is 48.4grains of H4831sc behind a 130 grain Sierra Game Changer. This load also works with 49.3 of IMR 7828ssc. I built this rifle on one of my spare Remington 1903A3 actions and a Krieger #3 CM barrel twisted at 8 and 26 inches long. I will use a coronagraph next time I'm at the range with this rifle, and report back.
