You don't shoot a 30-378 with light bullets. The best bet is a 200 grain Accubond and you can still get 3200 FPS with that bullet.

I never shot a light bullet in my 30-378, I really didn't like it much and sold it.

I did chrono a 300 Weatherby with a 24 inch barrel and factory Weatherby 165 grain bullets and got 3700 FPS on an Oehler chronograph. That is way to fast for any big game bullet...

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