105's seem to go to sleep in the 3300 fps max. 105's do not shoot well past 3300 as a general rule of thumb.
Weatherby brass sucks for holding pressure on the top end, and your expectations are to push the top end+.
You could do this with a 244 AI and save a bunch of barrel life.
If you go with the 244 AI or the 6/06 AI, you can push the limits on pressure by using PMC 7x57 brass or PMC 270 or 30/06 brass. Lapua is another option.
One thing that you should remember is that VLD bullets will not stand a .300 freebore.
