Stubblejumper,
How are you getting 3500 FPS MV? The Nosler 5th edition book shows 3362 max for RL19 which it indicates as the fastest load for 140 gra bullets (75 grains RL19-------3362 MAX)
To start with r-19 is too fast burning to achieve maximum velocity with the 7mmstw.Secondly noslers data for the stw's, ultramags and many of the weatherby mags is ridiculously conservative.