Per Nosler load data...
27 Nosler : 98.4gr total case capacity, 150AB @ 3.340" OAL = 89.9gr and ~400fps faster than 270win.
270win w/ 150gr AB yields 62.8gr capacity ... @ 52gr H4350 = 2782fps, 61.5gr MAGPRO = 2913fps
270WSM w/ 150gr AB yields 71.8gr capacity ... @ 60.0gr H4831SC = 2966fps, 68.0gr MAGPRO = 3187fps ... most accurate load 184fps faster than 270win, fastest load 274fps faster
270WBY w/ 150gr AB yields 79.4gr capacity ... @ 72.0gr RL25 = 3109fps, 70.5gr IMR 7828= 3207fps ... most accurate load 327fps faster than 270win, fastest load 294fps faster
So 27 Nosler gets me another 75-125fps over 270 WSM and 270 WBY options.
The real story here is that 277 finally gets bullet options for fast twist barrels with much better BC/SD/Energy/etc. like 264 and 284 options.
It will be interesting to see what other new developments that drives over the coming years!
