built new rifle in 378 weatherby, does anyone have a recommended starting load , would like to start with the hornady 250 grain gmx and also the the smk 350 grain, my barrel length is 30''. Live where its always windy need heavy and fast. Any input is always appeciated. Rifle has 1-10'' twist sst hart.

I'm using a near max load of H4831 with 270gr TSX bullets in my 378 Weatherby. If I look at the data for the 378 with 270gr bullets, the minimum is between 102.5gr and 104.5gr depending on the bullet mfg. The load I ended up settling on is above the max in the Barnes #4 Manual but below the max listed by Hodgdon with 270gr Hornady bullets.