RE: 300 remington ultra mag
I haven't shot any factory loads in my 300RUM and have been playing with 180gr Hornady SSTs and Retumbo. At 101grs of Retumbo average velocity is 3360 and 100grs is at about 3310. The acurracy is around MOA but more flyers than I want but then again I find that I am not as steady as I was two years ago.