I developed 1 load for my 338WM. I wanted the 225gr MRX to go 3,000fps and I got it. That's over the books and must be a MAX load in my rifle. Did not have standard signs of excessive pressure..the primers look just like the stock WW 200gr cheap'os I used as brake-in ammo...but, a few cases showed slight marks below the belt. Took 9 of them by the gun store and asked couple of the old timers to give me opinions on how close to the edge I was. They agreed with each other that I was most likely getting too much slide of polished case toward rear of chamber and into the bolt face. Seems logical that when ignition occurs the brass is slamed against the walls of the chamber and then is ramed back against bolt face more than normal cause the brass can't get a grip on the walls of chamber cause it's to slick! Just from a physics stand point it sounds correct. That 0000 steel wool made'em look like gold! I am not looking to go any higher than that load but would like to feel that I'm not .00001grs of H4350 away from blowing my self up. The most respected reloader said he would reload them 3 more times and then cut one top to bottom to see how much stretch the lower wall had done at the belt. Also, the Temp was 90 deg. = worse case scenario. What say you? Did lack of normal friction of case on chamber wall increase the smacking the bolt face took?